Hope this is related and helps someone. Our agency recently upgraded all GIS user computers to windows 7 on 64bit machines with IE9. We are stuck with arcgis 10.0 sp5 due to 3rd party software limitations so cannot say if this advice is relevant to 10.1 or 10.2 users.
After the upgrade, we immediately started seeing decreased performance issues with the basemap layers - specifically the worldwide imagery dataset. The basemap imagery would draw extremely slowly and often lock up and crash arcmap. We thought this was an issue with IE as opening it during an arcmap session would often cause an immediate lock up. We tried IE8 and found no difference. We moved to firefox and found some improvement for a day then it seemed like no difference again.
After a lot of frustration and numerous calls with ESRI, I narrowed things down to the map projection. Our local vector and raster (1-m res) data is in State Plane projection,so we tend to always work in state plane map projections. Saves redraw time and enhances editing. However, ESRI's 6" res worldwide imagery is in WGS_1984_Web_Mercator_Auxiliary_Sphere projection. That means that, in a state plane projected map, arcmap has to run algorithms to reproject the basemap imagery into state plane everytime you do something with your map.
The solution: A single 6" high res image layer can take much more time to reproject into state plane (or another projection) than even dozens of vector and low res raster data sets combined so, to speed up the use of ESRI basemaps, try puting your map documents into the same projection as the basemap layer(s) you are using - if worldwide imagery it is WGS_1984_Web_Mercator_Auxiliary_Sphere projection and allow your other layers to do the reprojecting. We found this to make an AMAZING difference in redraw time and arcmap 10.0 sp5 no longer locks up or crashes when using the basemap layers.
hope this is of use to someone....
