what does "unknown error 0xE80002d?" mean?
Are you on a windows or a mac?
I'm getting this error as well, trying to remove apps from my iOS4.2.1 iPod Touch 2g (8Gb). Using iTunes for Windows, v220.127.116.11. I can usually remove 2 apps per sync, then any others I've chosen to remove will get this error and stay on the iPod.
Retrieving data ...