Well, things haven't gone quite as smoothly as we like. There are multiple complaints about mail not actually being pushed through. This is totally expected given the number of iPhone and iPod Touch users in the wild. And it's likely millions upon millions of requests were being made simultaneously.
Plus this service is sort of free so can't really complain about that. It just shows the vastness of the mobile market, particularly the iPhone market.
Of more on Google Sync, here is a great post about it. You can see what Google offers at its sync page. And for more in the current Google problem, Business Insider has the scoop.
Personally, I'd wait a bit and see after the dust and excitement has settled down. I'm sure Google is working furiously to make adjustments and increase load capability. You can follow the Twitter updates to see how things are progressing as well. Is there anything Twitter cannot do?
I'm find it surprising that we even have this service. Let's hope Apple is truly studying Google Voice and engaging Google in trying to make GV work on the iPhone as it was meant to be.