Upstreams will be 400k on the standard products (ATM synch rate approx 450kbps) and there will be a full upstream option for businesses and those who wish to fork out a bit extra.
Line quality won't really be that much of an issue - if you can hit 4Mbit on the downstream generally you'll be able to manage 768k up.
LMFAO @ this though: Access to the most reliable and fastest Network in the world
Someone should mention to Pipex that they shouldn't be passing off UUNet / MCI's network as their own anymore
the Pipex authentication server was brought to its' knees by failure of a single network component a few months ago (thankfully just after I left). Their speed demonstration is nonsense as well, my 2Mbit certainly doesn't do 409kB/s.