Currently if you customize a popup using the methods recommened in your manaul for javascript you can not control the direction the popup opens. In many cases, the default logic then forces your popup to open completely out of view. I'll provide an example at the bottom.
We have developed over 20 sites with maps and not once has a customer wanted the default popup, they all want pretty and well designed popups that flow with their websites. Unfortunately the issue is forcing us to not coding future sites with esri because the popup (dojo one you recommend) can not be forced to open in a given direction. At the current moment we burnt two weeks of coding for a map we can't use cause the popup once styled can not be controlled
Here is an example. The popup on this page uses the "show()" function as described on this page, but beacuse it is customized the 2nd argument of "placement" is tossed out the window and ignored. In this example below every popup is being forced to open down and right, but as you'll notice, they don't do that. On top of that if you mouse over the upper right icon (furthest east) you'll notice the window chooses to open in the absolute worst direction, up and right so you can't see it. If anyting I'd almost beg you update your manual and let coders know if they customize a popup as you suggest they cannot control which way it opens and in some cases it will open out of the view of the map.
http://citgo.bvk.geoconsensus.com/esri/map_test_two.php
