I don't know if it sounds right..
I'm running the program on my PIV 2.0Ghz and my longest was 34h for one wu.
Currently it's doing wu's in 7h or so. It totally depends on the research it's currently working on.
When you go to the "Application" tab on the program you can see the current project.
The "Current Protein" and the number of Ligands it needs to process makes a lot of difference.
I only have completed wu's which has 27 ligands to test in the last weeks.. But a few weeks ago there were 30 to be researched and it took about 15h more to complete..
But you get credit for the cpu time, not for the job your working on. So if you complete two "small" ones in 15h or one "big" one in 15h, you get almost the same credit.
Good luck!