Wow. 30 Seconds To Mars, that really was a bit of a surprise for me, I totally didn't picture them as 'fitting the bill', they're way too...dramatically alternative. But I do like 'em, nonetheless.
And All-American Rejects was always a bit of a guilty pleasure for me, so that's pretty cool too. As far as the other band, I've never heard of 'em, but I download everything that comes out just so I can hear things I've never heard before and broaden my horizons (songs like Ever Fallen In Love, My Iron Lung, Heroes, and Rockaway Beach have become instant classics at my house, even if I've never heard of 'em before Rock Band).
Oh, and just to clear up the whole "young people" thing, I'm only 18 and I'm still anxiously awaiting Who's Next. Then again, I was raised in a family with good taste in music.