Brett_Tabke - 3:10 pm on Sep 3, 2010 (gmt 0)
Depends on how you are running the test.
Google allows classic split-ab testing without issue.
You could also do the tests on a time frame. If you now the index and listing rate, you could switch it day-to-day or week-to-week.
Either way, google shouldn't have an issue with it.