I think there's a good chance that the IE6, IE7 and IE8 are going to sound very good. Their frequency responses alone show that these are not normal IEMs with hearing aid drivers. All 3 go down to 10Hz! I really like the feature of the adjustable bass screws on the IE8. Different people have perceived very different frequency responses with the same IEM, I'm guessing because the different shapes of peoples' ears and ear canals--which effect sound differently for different people--don't have a roll in shaping sound with IEMs. The bass adjust screws will give you the ability to fine-tune the sound to your anatomy, not just your preference. For me the Shure E500 was by far the most ridiculously bassy headphone I've ever tried, and I absolutely couldn't stand them because of it; but I've heard other people call them bass light? A feature like this seems kind of necessary for an IEM that will work well for everyone. Those IE8s are coming out in April, and the IE6 and IE7 are going to be here in March. I wonder how much they'll cost. It looks like what Tyll told us a while back--that the new headphones would be dynamic, expensive (they look expensive, anyway), and unlike anything currently on the market--turned out to be true. Thanks to all those who spread rumors about new top full-sized dynamics and electrostats.
Still though, I can't imagine them sounding as good as top full-sized headphones, and IEMs are not a market I'm interested in. I've had nothing but bad experiences with them. I was really hoping for something I would sell my Edition 9 to try out. Oh well, they'll be perfect for a much broader market.
As a side note, M-Audio introduced a $499 triple-driver IEM as well. M-Audio has re branded some of Ultimate Ears' earphones. These look a lot like the triple-fi, but who knows, maybe they're tuned more like the UE10. Oh, and if you really want a new flagship full-sized headphone, take a look at Monster Cable's new $399 Beats, officially endorsed by Dr. Dre.