Maybe I'm behind the curve here, but having tried both forwarding and POP with gmail I say hands down POP is better. I found it annoying with forwarding, because I would get the email on my bb even though I may have been currently viewing the email.
I don't use gmail for business purposes, so if it is delayed because of polling woopie.....shit, I don't even care if I have a slight delay with business mail because I still respond much faster then if I had to wait to get back in the office. I also like being able to delete gmails from the server using the handheld [read spam] should I not need to save it and I won't be at my pc for a while.
One things for sure, regardless of how you prefer to set it up, bb's rock and have come a long way from my first one which was a 957.