I ran the HelloWorld sample and got these log infomation.
[PHP]04-16 14:56:33.104: D/dalvikvm(9369): Late-enabling CheckJNI
04-16 14:56:33.134: I/dalvikvm(9369): Turning on JNI app bug workarounds for target SDK version 7...
04-16 14:56:33.234: D/ArcGIS.LifeCycle(9369): map.onChildViewAdded
04-16 14:56:33.244: D/ArcGIS.LifeCycle(9369): map.initLayer
04-16 14:56:33.244: D/ArcGIS.LifeCycle(9369): >>>layer init startcom.esri.android.map.ags.ArcGISTiledMapServiceLayer
04-16 14:56:33.244: D/ArcGIS.LifeCycle(9369): layer init...
04-16 14:56:33.244: W/dalvikvm(9369): VFY: unable to find class referenced in signature (Lorg/codehaus/jackson/JsonNode;)
04-16 14:56:33.244: I/dalvikvm(9369): Could not find method org.codehaus.jackson.JsonNode.get, referenced from method com.esri.android.a.e.a
04-16 14:56:33.244: W/dalvikvm(9369): VFY: unable to resolve virtual method 4781: Lorg/codehaus/jackson/JsonNode;.get (Ljava/lang/String;)Lorg/codehaus/jackson/JsonNode;
04-16 14:56:33.244: D/dalvikvm(9369): VFY: replacing opcode 0x6e at 0x0005
04-16 14:56:33.244: I/dalvikvm(9369): Could not find method org.codehaus.jackson.JsonNode.getTextValue, referenced from method com.esri.android.a.e.a
04-16 14:56:33.244: W/dalvikvm(9369): VFY: unable to resolve virtual method 4784: Lorg/codehaus/jackson/JsonNode;.getTextValue ()Ljava/lang/String;
04-16 14:56:33.244: D/dalvikvm(9369): VFY: replacing opcode 0x6e at 0x000b
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): afterPerformResume
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): java.lang.NullPointerException
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at android.app.HtcAppUsageStatsListener.afterPerformResume(HtcAppUsageStatsListener.java:77)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2800)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:2851)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2234)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at android.app.ActivityThread.access$600(ActivityThread.java:139)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1261)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at android.os.Handler.dispatchMessage(Handler.java:99)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at android.os.Looper.loop(Looper.java:154)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at android.app.ActivityThread.main(ActivityThread.java:4944)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at java.lang.reflect.Method.invokeNative(Native Method)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at java.lang.reflect.Method.invoke(Method.java:511)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
04-16 14:56:33.244: E/HtcAppUsageStatsListener(9369): at dalvik.system.NativeStart.main(Native Method)
04-16 14:56:33.244: D/ArcGIS.TileCache(9369): max number of cached tiles:1000
04-16 14:56:33.244: D/ArcGIS.LifeCycle(9369): sdcache inited.
04-16 14:56:33.244: D/ArcGIS.TileCache(9369): SDCardCache
04-16 14:56:33.244: E/dalvikvm(9369): Could not find class 'org.codehaus.jackson.JsonFactory', referenced from method com.esri.core.internal.b.a.e.<clinit>
04-16 14:56:33.244: W/dalvikvm(9369): VFY: unable to resolve new-instance 717 (Lorg/codehaus/jackson/JsonFactory;) in Lcom/esri/core/internal/b/a/e;
04-16 14:56:33.244: D/dalvikvm(9369): VFY: replacing opcode 0x22 at 0x0000
04-16 14:56:33.244: W/dalvikvm(9369): VFY: unable to find class referenced in signature (Lorg/codehaus/jackson/JsonFactory;)
04-16 14:56:33.254: I/dalvikvm(9369): Could not find method org.codehaus.jackson.JsonFactory.createJsonParser, referenced from method com.esri.core.internal.b.a.e.a
04-16 14:56:33.254: W/dalvikvm(9369): VFY: unable to resolve virtual method 4760: Lorg/codehaus/jackson/JsonFactory;.createJsonParser (Ljava/io/InputStream;)Lorg/codehaus/jackson/JsonParser;
04-16 14:56:33.254: D/dalvikvm(9369): VFY: replacing opcode 0x6e at 0x016c
04-16 14:56:33.254: I/dalvikvm(9369): Could not find method org.codehaus.jackson.JsonFactory.createJsonParser, referenced from method com.esri.core.internal.b.a.e.a
04-16 14:56:33.254: W/dalvikvm(9369): VFY: unable to resolve virtual method 4761: Lorg/codehaus/jackson/JsonFactory;.createJsonParser (Ljava/lang/String;)Lorg/codehaus/jackson/JsonParser;
04-16 14:56:33.254: D/dalvikvm(9369): VFY: replacing opcode 0x6e at 0x0022
04-16 14:56:33.254: I/dalvikvm(9369): Could not find method org.codehaus.jackson.JsonFactory.createJsonParser, referenced from method com.esri.core.internal.b.a.e.a
04-16 14:56:33.254: W/dalvikvm(9369): VFY: unable to resolve virtual method 4761: Lorg/codehaus/jackson/JsonFactory;.createJsonParser (Ljava/lang/String;)Lorg/codehaus/jackson/JsonParser;
04-16 14:56:33.254: D/dalvikvm(9369): VFY: replacing opcode 0x6e at 0x001f
04-16 14:56:33.254: D/dalvikvm(9369): DexOpt: unable to opt direct call 0x1296 at 0x02 in Lcom/esri/core/internal/b/a/e;.<clinit>
04-16 14:56:33.264: W/dalvikvm(9369): Exception Ljava/lang/NoClassDefFoundError; thrown while initializing Lcom/esri/core/internal/b/a/e;
04-16 14:56:33.274: D/ArcGIS(9369): Failed to initialize the MapView.
04-16 14:56:33.274: D/ArcGIS(9369): java.lang.ExceptionInInitializerError
04-16 14:56:33.274: D/ArcGIS(9369): at com.esri.core.internal.a.a.k.a(Unknown Source)
04-16 14:56:33.274: D/ArcGIS(9369): at com.esri.android.map.ags.ArcGISTiledMapServiceLayer.initModel(Unknown Source)
04-16 14:56:33.274: D/ArcGIS(9369): at com.esri.android.map.ags.ArcGISTiledMapServiceLayer.initModel(Unknown Source)
04-16 14:56:33.274: D/ArcGIS(9369): at com.esri.android.map.LayerView.initLayer(Unknown Source)
04-16 14:56:33.274: D/ArcGIS(9369): at com.esri.android.map.MapView$1.a(Unknown Source)
04-16 14:56:33.274: D/ArcGIS(9369): at com.esri.android.map.MapView$1.call(Unknown Source)
04-16 14:56:33.274: D/ArcGIS(9369): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
04-16 14:56:33.274: D/ArcGIS(9369): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
04-16 14:56:33.274: D/ArcGIS(9369): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
04-16 14:56:33.274: D/ArcGIS(9369): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
04-16 14:56:33.274: D/ArcGIS(9369): at java.lang.Thread.run(Thread.java:864)
04-16 14:56:33.274: D/ArcGIS(9369): Caused by: java.lang.NoClassDefFoundError: org.codehaus.jackson.JsonFactory
04-16 14:56:33.274: D/ArcGIS(9369): at com.esri.core.internal.b.a.e.<clinit>(Unknown Source)
04-16 14:56:33.274: D/ArcGIS(9369): ... 11 more
04-16 14:56:33.274: D/ArcGIS.LifeCycle(9369): sdcard inited.
04-16 14:56:33.294: D/ArcGIS.LifeCycle(9369): map.onSizechanged
04-16 14:56:33.294: D/ArcGIS.LifeCycle(9369): !!! onSizeChangedSignal
04-16 14:56:33.294: D/ArcGIS.LifeCycle(9369): map.onLayout
04-16 14:56:33.304: D/ArcGIS.LifeCycle(9369): map.onLayout
04-16 14:56:33.314: D/memalloc(9369): /dev/pmem: Mapped buffer base:0x51fbc000 size:27017216 offset:24928256 fd:56
[/PHP]
I just update Android SDK 2 days before.