Alright, as stated in my other post, because our exchange guys have disabled "allow non provisioned devices" setting I had to search for an alternative device and I got myself brand new HTC Desire.

+s of migration from N900 to Desire that I've identified so far:

• Size: My very first thought was "oh man, its so slim". Desire is twice as slim as N900 with more or less same weight.
• Screen: you do not lose anything, colors seem to be even more colorfull than on N900
• Portrait mode.
• Native support of active sync. Finally! It works with my exchage 2007 and it rocks. Vitaly, no offence, but compared to Andriod implementation of Active Sync, one on Maemo is not even worth comparing.
• Google maps. I missed it on maemo.
• Browser almost as good as in N900.
• Appstore or however they call it. No "wait a little community will develop something".
• Nokia's charger and DC-11 compatible with Desire

Now -s

• Browser, almost as good as on N900, but flash support is bit behind. On the other hand if you do not need to listen to to last.fm via broswer (which N900 did perfectly) then you won't spot any difference.
• Bluetooth\Browser: Desire can't play sounds that web-pages produce via BT.
• Camera. N900's camera rocks and will rock. HTC is waaaay behind here.
• Shell. Well, ok, I won't be able to administer my remote linux box that easy and "nativly" as I did it on N900, but honestly - I can wait until time permits to do so from my laptop.
• VPN. VPNin into corporate network and accessing servers remotely was somewhat handy, but I can live without it.
• Keyboard. I'm going to miss it much as I will miss good N900 camera.
• No native skype\IM support.

Ok, my verdict: Desire is in almost all dimentions as good as N900 or even better. Key ones for me are email, browser, camera, keyboard.
Email experience is by far better on Desire.
Camera on Desire sucks. Hoever if you need it only for taking party pictures, to recall what has happened last night, its absolutely acceptable.
Browsers are equally good.
Onscreen keyboard is ok, but hardware one really rocks.

I'm staying on Desire and so far I love it and recommend it anyone who is looking for a geek-top of the range-phone, not linux box with GSM module.