I'm about to buy an arduino, and I can't figure it about which arduino its better , I mean, the nano has the SAME "power" as the Duemilanova? and its just a small version? or whats about it
For a first arduino, I'd recommend a full-sized version like the duemilanova. All (almost) of the tutorials are written around that format, you'll be compatible with off-the-shelf shields, and it's slightly cheaper too...
I want to back that up. Duelmilanova, also known as the 2009, is a great board to get started with. It's also included in many starter kits, so maybe you should buy one of those rather than just a board. There's a good list here:
It's not so much which is better, but as a beginner you are better off starting with an Duemilanova. If you damage the socket mounted processor chip (it happens frequently as part of the learning curve) it can easily be replaced for $6, but with the Nano you would have to deal with the small SMD package, trying to unsolder and solder a replacement processor.
Lefty
Arghh... Has someone invented a new board or something?
starting with an Duemilanova
Duelmilanova, also known as the 2009
full-sized version like the duemilanova.
Duemilanove!
Duemilanove - This is the latest revision...
Not Duemilanova
But the duemilanove is better to use for prototyping projects. The 328 chip can be remover/replaced and used standalone, all shield fit it, it doesn't need a breadboard to use and it's easier to use on the whole.
Mowcius
Duemilanove!
Quote:
Duemilanove - This is the latest revision...Not Duemilanove
You sir have just received a cyber-slap.
nano sits on a breadboard sucking up valuable space, the big models sit off to the side and you just jumper what you need over
Me too - I recommend the Duemilanove as well, mostly for all the reasons folks have already stated. I think the biggest thing is all the tutorials are written for it.
What I do is develop on the Duemilanove and then use a Pro Mini or one of the other very small boards for the final product. My '09 remains attached to the breadboard for the next project.
duemilanova or be like me and get the mega because its more powerful and alot easier to pronounce/spell 
because its more powerful and alot easier to pronounce/spell
Now that's the best justification for buying a Mega that I've heard yet. 
Lefty
Can we please have a petition started to change the name of the Duelm... the 2009 to something simpler... like the "Arduino Core" or "Arduino X"... you know, the less letters the better!
The 2010 board could just be named "AX". 
I started a revolution!!!!!!! ;D
could just be named "AX".
It's from Italy. "AMMX"
(but "MMX is a trademark of ... someone else.)
yeah, something simple, arduino XXX! lol
arduino
As if Arduino is easy to pronounce. ;D
The should just call it Joe X.
Lefty
nahh, just BOB!
(but "MMX is a trademark of ... someone else.)
You can't trademark a number ;).
Can we please have a petition started to change the name of the Duelm...
Just shorten it to Arduino Duel...and for the main basic board, call it the "Arduino Duel" core board. Not to be confused with the innovative "Arduino Dual Core" board.
You can't trademark a number
Well it's not a trademark (that I know of), it's used by intel on some processors 'MMX technology!' among other things
Mowcius
going back to the main topic lol
well thank yall for your responses,ill buy the "2009" arduino xD