Actually, yes. It more accurately shows what people want to buy and regardless of whether that means more number ones or not, songs will reach number one if enough people purchase it. The fact that we only have like 8-9 number one singles a year is enough reason to change

It could really help certain people's faves in promo as well. People seeing a "Single" released to iTunes instead of it just being left as a random album track will draw more attention to it. I remember US iTunes doing that back in 05/06 a lot.
Edit: People here are too obsessed with longevity. Like who wants a song to remain popular for 4-5 months

Any song gets old after two months max.