So my copy arrived this morning, been playing non-stop for the last 7 hours. INCREDIBLE.
The only down side is that the graphics are too weak for my 48" TV, so it looks really pixelated/grainy. My tiny TV looks stunning, though, unfortunately.
Anyway, I haven't managed to unlock Trevor yet, only done about 8-10 missions and spent most of the time exploring the map. It's HUGE, never thought it'd be this big. My fave part so far is getting into a convertible and racing to the top of the Vinewood hills. I did it at sunset and it was stunning.
My most impressive feat so far was being able to land the jet at the airport, haha, my mum was shouting at the TV because she thought I was gonna crash. I landed it, but the cops got me when I got out anyway.
The missions have been good so far, except I gave up on my current Franklin one because I still can't find Lamar part way through.
Seriously can't wait for GTA: Online!
Also, like some people have said, the driving is much better in this one. I was even surprised at how well I can handle the chases etc.