I don't sell much at Smashwords, but the number of books I've given away this week (all my books are free during RAEW) is about the same as the total number of books I sold at Smashwords last year. I suspect free gets a lot more downloads than 25% or 50% off.
I've also noticed that four people have now added me as a favourite. Last time I looked there were two, so I suspect two of those have appeared during this week. I can't be certain, though, because I didn't check at the start of the week.