As the title says, file this under rumor...but one that may be detailed this Tuesday, the 24th.
According to @MS_Nerd, who has an interesting history with leaks from within Microsoft, the Zune services as we know them will be broken apart, presumably in response to the Nokia deal, which is making some of the backend redundant:
"Wee little rumor seeping out now: Zune next to be split into Xbox mobile, Xbox Live & Windows Live Zune on the 24th."
"And the Zune backend platform will become a "Nokia services on Azure" offering, with content from Netflix, Last.fm & Hulu among others."
If true, this comes a little more than 2-years after the first Zune team was broken up into hardware and software services, with the former being absorbed under the Windows Mobile group. Now it's the latter which is being divvied and presumably gobbled up by other divisions within the company.
There's been talk for awhile now of "Zune re-branding" and something happening within that division, so this isn't too far fetched. We'll see what happens, if anything, this Tuesday.
Source: @MS_Nerd 1, 2; Thanks, Amir, for the heads up