I have noticed some strange behavior. One of my sites had 50,000 pages indexed over a period of 5 days last week. Then nothing for 4 days, not a single visit. Then yesterday my logs showed another 4,500 pages had been visited. I would have thought that once it was done, it wouldn't visit for another month.
Same behavior noticed on three sites for me. Seems like something is going on. I wouldn't be surprised if the update was a bit late this go around. Maybe there was a problem with the initial spidering or maybe they want to get more pages into the dance. I don't pretend to know but now I'm more interested than ever in the results of the update.