i'm a linux user on my desktop pc, I love all the geeky options of the N900, but in the end I use the N900 as a media device:

32Go + microSD + FM transmitter + native divx support + photo quality + stereo speaker + kickstand + lens cover + good battery autonomy

For me all these MEDIA features already justify the N900 to be the best entertainment device available (and I would need MORE than 48Go to put my music only), better than the coming HTCs or the just-annouced Dell phones. And people seem to forget that they won't find these options in other phones, for me they are a lot more useful than a 4.3 screen or a 1Gz snapdragon

And when you add the OS and the geeky side, I don't see any upcoming competition