I have to admit, I was expecting more WP8 W8 synergy, such as iPhone/iPad.
Microsoft synergy seems to be around the tablet/PC, and after owning a WP8 for a month now, it seems that windows phone is not a high priority line of business for Microsoft. This shouldn't really come as a surprise though, because if you actually look at the numbers, Microsoft's Electronic and Devices business is "only" $3-$4 billion dollars per quater (which most of which is probably Xbox). Compare this to Apples iPhone line of business, which is $30-$40 billion (Apple also however makes their own hardware of course).
This lack of synergy is one of the biggest flaws I think of the Windows Phone ecosystem. If Microsoft want to be a serious player in this space, they need to break into the phone market through the PC (their biggest strength). That is how Apple broke into their market, via the phone.
The tough part is that the smartphone market is becoming saturated. This is bad news for Apple in a way, since such a huge portion of their revenue is tied up in that one basket, which is why I expect them to release some sort of iOS TV that uses an iPad or iPhone as a remote. It also means however that the Windows Phone platform will probably remain small for some time, kind of like how Mac's are in the PC world, until Microsoft can release a unified platform across their entire ecosystem.