Apple isn’t known for rolling out ‘clones’ of anything. What they are known for is taking existing products & technologies, and packaging them together into a new and innovative product (mp3 players, smartphones and tablet computers all existed long before Apple revolutionized those markets); don’t expect their streaming music service to be any different. A few things they can do to make a streaming music service more ‘Apple-y’:
Make it an expanded version of Genius playlists, so it has access to all your purchased iTunes tracks (local and iCloud), as well as Apple’s full library of music you don’t own, streaming from the cloud. This way Apple only has to pay streaming royalties on the songs you don’t already own, giving them a leg up in profits over the existing streaming-only services, and perhaps cutting down on the number of ads you’re served. Songs you don’t own will show up in your played history, but can’t be added to your own custom playlists unless you buy them. Buying would be as easy as clicking the ‘buy’ button on the song entry, as though you’re in the iTunes Store. This way they’re able to use the streaming service as a trojan horse for the iTunes store, introducing you to new songs based on what you already like, but limiting what you can do with those songs until you purchase them. Some customers will just use the service the same way they currently use Pandora, in which case Apple won’t make much money on streaming royalties, but at least they won’t lose those users to Pandora/etc. Those customers are also that much more likely to make any potential music purchases through iTunes.
At least, that’s what I would do if I made the decisions at Apple.