My Mail app is acting weird with Gmail. If I leave the mail app open, and come back to my phone after several emails have arrived, I can only see the 2 or 3 unread emails. I hit refresh and nothing else is there except for 2 or 3 unread emails. If I close the mail app and reopen it, then everything in my inbox appears.

It used to be that my Pre's inbox would exactly match my Gmail inbox. If I marked an email read in Gmail, when I look on my Pre it reflects the same email read. After 1.3.5.1, unless I actually read the email on the Pre it will not mark it as read even though I've already read it on my PC.