How many subscribers might Apple Music have by year's end? And how many trial subscribers will turn into paying customers? Music-biz blogger Mark Mulligan, in a guest post on Hypebot, hypothesizes that the service will attract about 5.2m trial subs per month (1.2m of these being family subs) and 41m by year's end, with somewhere in the neighborhood of 8.7m active paying subscribers.

The trial number is based on a slowdown from the current rate of 315k trials per day to 170k per day, and the paying number comes from a 25% long-term conversion rate. Apple doesn't get to 100m in its first year, but counting anyone who ever subscribed (including all members of family accounts) gets the service near 70m.

None of this apparently factors in Apple advertising and marketing for the streaming service, which has been limited to the free Beats 1 radio side. It's thought that Apple will wait for its next full iOS update to do a full-court press on the service, having worked out more kinks. Meanwhile, speculation continues about the service's Android version, said to be due this fall.

In any case, Apple will end 2015 as the #2 streaming service mere months after launch. How long before it becomes #1? Hard to say, but remember: Apple can wait. This isn't its core business.