Same problem here...
AW-stats: users & bandwith are about 50 times lower, a site with 10000 visitors/day has now only 200/day
Webalizer: switched to Webalizer-stats for a certain domain, same problem
Statistics in Plesk: Traffic for domains (under "Report") are also 50x too low. Users pay for extra traffic, so I'm loosing money now...
Please SW, we need a solotion - sooner, not later!