[hwatson]

Considering that 100Mbit/s is 12.5MByte/s, the speeds you're seeing aren't horribly distant from your "up to" speed.

[For reference's sake, 8MByte/s is 64Mbit/s and 9MByte/s is 72Mbit/s

[JoshTriplett]

The usual rule of thumb I've seen for incorporating protocol overhead is to divide by 10 instead of 8: a 100Mbps connection can usually download about 10MB/s in practice (over http, scp, rsync, etc).