What The Google Is Going On At MIcrosoft?

Yesterday afternoon the Twitterverse - and several at least semi-respectable sites - exploded with rumours that Google would b e on-stage at Microsoft's Device event later today. Given Google's very limited support for Windows and Windows Phone - the twin focus of this event - its hard to see why.
Or is it?
So far the rumours have seen Google announcing official versions of its core mobile applications for Windows 10 Mobile, universal app versons of the same, supporting both desktop and mobile; and wildest of all Google Play arriving on Windows 10 Mobile.
In terms of making no sense at all this is one rumour that has it all. Google and Microsoft are in a bitter war over Android, Search, Desktop, Browser... everywhere basically. This week's announcement about an end to patent battle hostilities doesn't really go all the way to ending the war.
I think we can discount the possibility of Google Play arriving on Windows. Doing so would be something that supported the old Microsoft Devices and Services model championed by Steve Balmer. In the Nadella 'Mobile first, cloud first' world giving Google the keys to the Windows app store (which this would effectively be doing) would be a self-inflicted blow of some force.
Google apps for Windows Mobile? That seems more likely. Given that Google makes its money from people using apps like YouTube there's every reason to come up with a good Windows Mobile client.
Will these apps be universal though? Seems logical to build apps that will run everywhere if you're going to build them.
I'm still more than a little skeptical that an y of this will come to pass. Especially as Microsoft's event will be mostly about hardware.
At least we don't have long to wait to find out.