>>usher just got a huge block of sales added - enough to challenge for #1. What would cause one artist to dominate a segment of the overall sales like that?<<

I dont know , man . I've watched the building hits daily double chart for a few months now and every week , some album(s) get a slew of sales late in the update process, while others that start fast , slow down considerably. Their preview articles that state the projected sales mid -day on Monday are usually right on (except this week , where they didnt even mention Prince??)

It's MY fault, ya'll. I bought Usher's album this weekend.