High CPU for the first 5 minutes after installing

After installing iTunes 10 and launching for the first time, the interface was acting a little sluggish. Scrolling was a little delayed and the Ping invite screen popped up but remained blank. I noticed one CPU was pegged at 99% for about 5 minutes or so. I left iTunes open, let it continue and then iTunes' CPU % went back down to 1%. All signs of sluggishness disappeared. Suspect their is some type of migration or setup that it is doing beyond the usual 'converting library' activity. Library has about 6,000 items.