… it just might be your photos
I recently upgraded my phone to 4.3 and had exactly the synching problem discussed in this article. I solved it – mainly through trial and error and really wish I had seen tis first – because now I look back – the solution describes exactly what I did – (amongst a tonne of other things.)
first unchecking syncing and then re-syncing everything (which took a while, as all of the photos were re-optimized and copied over) worked just fine. So, at least for me, there was a problem with syncing photos, and in both cases, deleting the photos and then having the computers and iDevices sync all photos, events and faces solved the problem.
Full Article :: Problems syncing after iOS 4.3?
Passed on – with thanks to :: TUAW – The Unofficial Apple Weblog