5.1 update delete Safari bookmarks iPhone 3G

Last time I did the software update to my 3G iPhone, all my bookmarks in Safari (on the phone) were deleted.  I was very unhappy about that, so I've been hesitant to do the latest update, because I don't want it to happen again.

Is there some way to back up Safari bookmarks, so I can put them back on again if they're lost?  I'm very hesitant about syncing/updating things, since I always manage to lose lots of stuff on the phone whenever I try to do something

(On another related note: I sync my phone to my main computer profile.  But sometimes I plug the iphone in to charge when I'm on a secondary profile, and don't have it sync.  One time I did that, all the Safari bookmarks in that profile copied over to the Safari on my phone, and all the Safari bookmarks on the phone copied over to the Safari in the profile.  I don't know how it happened, or how to reproduce it if I need to restore my bookmarks.  And it only happened once; I don't think it's ever done that again, and not ever on the profile I sync with.)