When I stay synched to the network how much upload bandwidth does it consume on average?
if you don't put any limits on it...... random.
depends on how many people connect to you that are missing blocks, and what your max upstream is
that is my bandwidth usage, 98% exclusive to bitcoind. rest of the data would be me just checking out log files and such.
that's with 800-900 connections
if you don't allow incoming connections, you'll only have 8 (I think)