I have been a long term fan of smartphones - all in one devices which let you do everything out of the palm of your hand, for some reason I don't want to be seen with a phone, a camera, a camcorder, an ipod.mp3 device, blah blah!!
My non-smartphone foray started with sony t310 and ended with t610. Having worked for Nokia (security division), I was frequently told by HR that they were willing to give me the Nokia 9000 brick or any other nokia phone I desired. But no I was a rebel and went for my first smartphone, an O2 XDA2s (for 45k!!) and that was it, never looked back.
Its been a long journey since then, and along the way I have experienced smartphones from palm (treo), samsumg (blackjack), LG (viewty) and recently blackberry (bold 9000). I used to see all the apple fanboys around me running their cool macs and iphones and ipads as well as the windows fanboys with their win7 laptops and windows mobiles phones. But I was always an open source person and stuck to using linux as my primary OS on office laptop as well as home laptop. The only anomaly in my open source world was my smartphone, always closed source, always proprietary and always controlled by the service provider or hardware manufacturer.
I looked at Liinux Mobile (LiMo) and realized it just wasn't there and then came Android from Google. I knew this was going to be big but waited to jump in till I got bored of blackberries and winmo phones and finally made the jump in June and ordered my first open source based smartphone the Nexus One directly from the Google store. Got it with the car kit and custom engraving and all

(for 600usd)
The long wait ended when I visited US on June 14th and got united with my nexus one. There has been no looking back with this most excellent piece of hardware since then. The best part is the phone is unlocked and has no SP or vendor branding and will for a long time be the first phone to get every new release of Android from google (provided minimum hardware specs are met)
I upgraded to an interim Android 2.2 release (manual update from leaked google build frf83) and then got the OTA (over the air) update yesterday and am now on the final Android 2.2 (froyo frf91) build.
Pros so far
1) Excellent Amoled screen with vivid colors and excellent sharpness
2) Working exchange email with contacts and calendar syncing. gmail/gtalk/facebook/twitter apps are great and fully functional.
3) fantastic bundled apps and the android market has apps for practically everything you want
4) shows a consolidated view of contacts on outlook and in google contacts with direct integration into all modes of reach including phones, email, facebook, gtalk, twitter, et al!
5) Excellent car kit - google turn by turn voice navigation (get brut maps to make it work outside US) which works really well with the car kit. I can now play music/video on car speakers, get directions and take calls from the car kit seamlessly without ever having to touch the phone
6) google voice search/typing and google goggles are really great to have. the onscreen keyboard is great and takes care of your mistakes while typing. 270 degrees screen rotation makes life great!
7) really fast with android 2.2, full flash support (watch online videos on natgeo, etc or play any flash game - eat this is apple) and pinch to zoom in browsing and images.
8) no proprietary BS, no special connectors or wires - all standards based mini usb, bluetooth and so any accessory just works!
9) great camera and video recording with flash/led light for pics/video
Cons
1) not a con but did get a clarivue ultraclear screen protector (10usd free shipping) as everyone i know wants to play around with the touchscreen!
2) built-in corporate email client is presently text only (no html) and signatures are appended only in new emails not forwards/replies.
3) only outlook/google contacts are available, but cannot browse the corp global address list (gal) for phone numbers of office people. GAL is available to complete email addys in the email app though.
Overall I am very happy with this device and I would whole heartedly recommend anyone to go with this over the winmo or iphone or blackbery.
Ofcourse if you are one of those apple fanboys by all means go for the iphone 4g.
For my open source brethren this linkie is fun
The Right and Wrong Ways To Hold an iPhone and so is this video