Actually, I don't see how the idea in and of itself will benifit modem users any more than it will broadband... perhaps I've missed something.

From what I can tell, the only reason everything isn't hunky dory right now is due to three issues.

1. people don't understand what is happening. and get upset over something that really isn't happening.
2. the number of ultrapeers is still low.
3. people are 'hacking' their way into being peers even though they aren't willing to commit the time or bandwidth to actually support that, screwing their clients when the peer drops 30 minutes into a session.

None of these things are affected by your connection type.

since modem users are unlikely to become peers without 'hacking' in the new 'world order', this should actually help things. You no longer have to worry about 3 of your 4 connections (or however many you have) being eaten them.