Can I prevent ICS browser from using CPU while in the background (without back-button exiting)?
I have reason to believe that this may be a bug caused when the Web app has a large number of bookmarks.  In System Settings -&gt; Accounts and sync I turned off Sync Web under my Google account.  Then I went to Manage Apps, clicked the All tab, and hit the Clear Data button.  

This reduced the usage of the Web app to 1% when in the background.  

When I enabled Sync Web to import all my Chrome bookmarks, then disabled it, the problem showed itself again.  I reproduced this problem twice.