ive got the same concerns about the laggy screen.
not so much as the touches not registered but at the overall dropping of framerate and not-being-smoothness.

i've beginning to look at it this way: i've used all the windows'es available on my desktop, than i tried an apple computer. and i have also had linux installed (wasnt much more than an install though, tar.gz really didnt mean anything to me and so it was back to windows quite quick) but the thing was that from all these OS's linux was the most slim OS i used. by slim i mean as less fancy stuff, ram and cpu eating *****.

So when ill get my n900 and its laggy, i can only imagine how laggy the other OS's would be with the same possibilities, hardware, graphics etc.

relativation my man, relativation is the key.. the key to the chest in super mario bros 3 (most left chest usually contains the flute)