Another new poster here, been lurking for a while..
I'm debating over the 5680 and the 4X80 when it releases in Oct.
They are both very very nice, but I am not looking for a desktop replacement, as my desktop is decked out already. I am looking for a sexy, portable, fast laptop I can take to work with me(ISP Tech Support), do my day to day stuff(forums, browsing, web design stuff), and of course play games..
There are differences between the 5680 and 4760, but when the 4X80 releases it will be a VERY close call. The only remaining factors at that time will be the extra battery the 5680 sports, screen sizes, and overall size of both machines.
I LOVE the widescreen on the 4760, but the machine looks very big and not as portable, and I don't know of a Targus backpack or anything like Targus that will hold the sucker(I may be wrong on this). The extra battery on the 5680 is also nice, but I will probably have whichever I buy pluged in most of the time so thats not as big of an issue.
I'll wait for the 4X80 and then decide, I have some cash to save until then anyway.