iTunes Sales Level Off?

With the whole "Apple moving to Intel" thing, I think there is another issue that's being over-looked: it seems iTunes sales may have leveled off.

I have been recording the data Apple releases about iTunes sales from the beginning. Using their "total songs sold" number and the date of the announcement, I've been able to get a good approximation of how many songs they're selling per day, going back to when the iTunes Music Store was first released. During his keynote yesterday, Steve Jobs claimed total iTunes sales of 430 million, up 130 million from their March 2 number.

This yields an average songs-sold-per-day of 1.35 million. That doesn't sound too shabby until you look at the last period where the average was also 1.35 million, marking the first time since September 2003 that the per-day average hasn't significantly increased. Is this the beginning of the fall of the iTMS?