I've downloaded about 20-30 on Beatles and 3 free rock band songs. I'm going to get a bunch of songs next week though, once I get the first two games from Amazon.  Dont have any for GH, cause I dont own any Guitar Hero games.
So, how many songs do you Giantbomb folks have downloaded?

Uggh. Far too many. Like hundreds... upon hundreds.

I've got about a hundred for Rock Band, and I have 3 for Guitar Hero. 
 
Yeah, the Rock Band store is not only better music-wise, but it makes it much easier to find something awesome.

Overall, probably 25.  Around 20 in Rockband and only around 3-4 in Guitar Hero.  I only buy a handful of DLC that I know I am going to play more than just one to two times.  They kind of have to be some of my favorite songs.

I just picked up Rock Band so far I've only downloaded 3-4 Blink 182 songs... Just to jam around with the kids at home.

I downloaded a whole Beatles album, and probably 10-15 RB2 songs. So that's like 25 songs. I think it's too many. I feel like it was a waste of money, except for The Beatles, but I kind of downloaded them once I was starting to get tired of the game, which was a bad idea.

Less than 30 I'm sure.

I stop counting after 300, that was ages ago. 
 
EDIT: I've only got Rock Band 2 and didn't get anything for GH WT... when I had it.