I get the redraw issue and I've not rooted and using the stock Samsung launcher.
Lots of the time it takes about a second to redraw widgets and such, and I've had it a few times now where the entire background goes totally black for about 5 seconds till it is redrawn.
I've had it once where it didn't redraw after a minute, I went to bed and it had fixed itself by the time I woke up.
On a different note - how does the phone/drivers work with OSX? Will I be able to plug the phone in via USB and drag and drop like I do now?