At work, we compared a desire and my n900 for a few hours in different things. My N900 runs at 800mhz, with official software. The desire with the latest update...

Camera - Desire, sharper, better colours
Video - N900. Better framerate, more detail.
Media - N900. Plays almost anything you throw at it. Speakers are great. Not a full reliable app for Desire for divx ect. Yet.
Touch screen - Draw. As usual, resistive is more accurate, capacitive more sensitive and fluid. Only just though.
Internet - N900, easily. Flash is miles ahead too, the Desire runs out of memory constantly, and the lack of stylus is a pain on a high res screen.
Memory - N900. Obviously.
Looks - Desire. Slimmer, nice finish on the back
Display - Desire. AMOLED looks beautiful. High contrast, vivid colours. Not much between, but enough.
Apps - Desire, as in more variety, better system to deliver the apps, and you get the feeling it will always grow.
OS - Draw. I love android for its usability, but you cant beat how open maemo is.
Social networking - Draw. I dont give a rats about facebook, but they both do well, both have widgets, the n900 has the bonus that is can handle 'full' facebook with all its flashy glory. Twitter ect is also so very lame, but is equally supported on both.
Call quality - Desire. Excellent speaker volume. Clearer then n900
Games - Desire. Better choice of quality games. Although Duke certainly puts up a good fight.
Battery - Desire, although still not great.

N900 gets super brownie points for an awesome qwerty.

By the time I was done, the Desire really didn't convince me in anyway that it was a 'better' all around phone. Of course, everyones looking for something different, but if you already have an N900, you already have the best out there.

been looking at the desire myself.I have to admit,i know how versatile and wide open my 900 is and what potential it has.But you just cant help being tempted by the flash young thing called desire.Even when i have it in my hand and being wowed i still have this little voice in the back of my head telling me its beuty is only skin deep lol.I was also let down by the N97(even lost all the money for it,scammed on ebay when selling it) but the browser on the 900 and the FM transmitter are two luxuries i could now not do without.

For me its all about the web browser at the moment. There is nothing that comes close. My gripes with the N900 are more directed at a lack of support from Nokia. I know the smarty pants on here are doing amazing stuff, but at the end of the day, the 'big' changes (mms, the changes in 1.2 ect) can only really come from their end.

The Desire is stunning, in hand and having a blast on that awesome screen, its definitely one of the 3 top phones available at the moment. The N900 is literally the only phone at the moment that isn't beaten hands down by the Desire (Yup, that includes the x10m iphone, the awful, awful droid, and absolutely anything symbian based of course)

If you end up with it, you'll be ecstatic, honestly. You probably will never regret it either. Its that tight between the 2 phones. What may sway you, as I said, is the support that Android has, and to know that the software, and hardware in there, are both pretty future proof, especially with the announcement of how excellent Fro-Yo looks to be performing.

i read ur other post and i was meaning to post and say 265 was waay under value . good thing u got ur money back though.