I'd like to add to the discussion as well by typing up my little comparison between th N900 and the Samsung Galaxy S (Vibrant). I had an N900 which I sold and finally got a Vibrant on a deal that was too good to pass. There are my personal opinions and experiences which I thought would be worth sharing because they might be beneficial to anyone trying to compare these handsets from a general user's perspective. I am aiming for objectivity in this comparison because that's how I look at my experiences. Should there be any bias, consider it human and let it slide.

Hardware:
Build wise, the N900 was superior by leaps and bounds. It was a typical Nokia handset which screamed SOLID and built to last. The Vibrant feels like its made from cheaper materials, even though its very much more sleeker than the N900.

So far, I miss the invincible feel the N900 had but also love how I can't feel the Vibrant in my pants' pocket. I loved carrying the N900 around without a carrying case and just a screen protector but can't take that chance with the Vibrant because of the flimsy hardware materials used. Taking pictures with the N900 was a great experience because all I needed to do was slide the camera shutter and shoot. With the Vibrant and a lack of dedicated camera button makes the camera painful to use, coming from the N900.

The radios, be it wireless or GSM, are way better on the N900 again. This should have been a given but they came to me as a surprise on how weak they were on the Vibrant. This was particularly noticeable in low coverage areas and steaming music while driving. I am aware that it also depends on the software used, but the Vibrant has dropped more calls and has a generally lower in-call quality in terms of reception as well.

On-board speakers are the same as well where the year old stereo speaks on the N900 outshine Vibrant. The sound was crisp and clear on N900 whereas it sounds muffled on the Vibrant. Let's not forget the intuitive QWERTY keyboard on the N900, the N900 had the hardware a smartphone should have. I didn't mind the bulk or the spacing of the "space" key, which I thought worked better on the a keyboard that size by reducing travel and letting the right thumb do the work.

The only thing that the Vibrant has over the N900 is a Super-Amoled screen. Both in size and beauty. If you want to demo something on a mobile, the Vibrant's Amoled is the way to go. Everyone, and I mean everyone that has looked at the screen on my Vibrant has dropped their jaws. Add to that a live wallpaper such as that one with ripple effect, you get to have fun with the "oh I'm jealous comments", especially from iPhone 4 users.

Software:
The Vibrant is running on Android 2.1 (Eclair). A 2.2 update is due pretty soon on the stock kernel. This is my first Android handset. The first couple of hours went by cursing out the very unintuitive way in which Android works. For example, the presence of hardware keys on a touchsreen phone. The presence of a "back" button where it should have all been controlled within the confines of a screen. Symbian^3, Maemo and iOS are great examples of this.

The need of hardware keys on Android could have easily been eliminated and I consider this laziness on Google's part. If they call it differentiation, it is not a very good one in an era where touchscreens dominate. After overcoming this barrier, Android is a very pleasant experience. The Vibrant is FAST. It is snappy and the Hummingbird processor impresses. Everything loads up instantaneously and load times are now a conceptual phenomena. The N900 on the other was quick, but obviously not as fast as the Vibrant. There are times where I am amazed of how quickly everything works on the Vibrant. The N900, to me, definitely could have improved, where wait times could have been eliminated and the software could have been refined for that purpose. The upcoming Nokia N8 is a great example of that.

The Vibrant is a great example of "just works". After having dealt with Maemo and sometimes having to troubleshoot it like a computer, Android is a breath of fresh air. But where it shines, there lies its greatest weakness. The lack of multitasking. The year old N900 still shines in this area. This is why the N900 felt more like a mobile computer than a smartphone. I loved having the ability to do a number of things at the same time especially when communicating with different people at the same time. Android has a long ways to go before it can come close to Maemo in this regard. So going from an uber geeky handset to a consumer aimed product was a nice change. And if anyone is tore between the two, the choice would be down to which side you prefer most? The consumer friendly side where you want things to just work or the uber geeky where you wouldn't mind missing a call or two for the sake of a hack that you are working on.

Nokia wasn't kidding when they said that it was meant PURELY for development purposes. I am surprised they didn't turn it into a development product like the LG Windows Phone 7 handset. In terms of sheer potential, the N900 still has the edge over anything other smartphone on the market.

In terms of connectivity, both phones are equal. One has better hardware and the other has better apps.

Overall:
It comes down to preference. This has been my slogan lately if people ask me what phone is better because most smartphones today can do it all, one way or the other but it's what you want from it. The N900 was a great experience for the geeky side of things. I learned a lot in terms of how things work in an OS, both on a smartphone and a computer. The Vibrant is a nice review of what Google's upto. Android too, has a lot of potential and is very impressive. So right now, I'm in love with the Vibrant because its a consumer device that just functions the way you want it to.