acoustic guitar-size/model differences

can anyone point me in the direction of or answer the following-

what are the differences in acoustic guitar models? benefits/styles of music better for/differences in tone/etc... of dreadnaughts/om/ooo/jumbo/auditorium/etc... the line in martin catalogs that x size is better for fingerstyle/blues gets a little old. why is it better?

thanks in advance.

Excellent answer, but I'd like to add that you should probably just go into your favorite music store and pull some guitars off the wall and play them.
While a 000 won't have the low end of a dreadnaught, it's definitely more comfortable to play, due to it's thinness, and a change of string types and gauges can change the sound of any guitar quite a bit.

Also, the choice of woods can make a difference, too, biasing a guitar from treble to bass, regardless of body style.

The other difference would be in neck width, where a wider neck lends itself to fingerpicking a bit better than a narrow neck. Problem is, if you are used to a narrow neck, like on most electrics, your fingers will not fall into place until you get used to it.

I got a 000 as it had a good all around sound, and is way more comfortable to play than my dreadnaught. I passed on the wider neck some models have, as my fingers just couldn't seem to find the chords and notes.

thanks to you both!