The rumors are coming from the Twitter feed of SamFirmware, a website dedicated to Samsung news and (not surprisingly) firmware for Samsung devices. Apparently, the rumor is that Samsung is going to stop supporting Windows Phone 7 by the end of 2012, and will likely only release one more WP7 device before pulling the plug.
There has been no comment by Samsung on the matter, but given the success of its Galaxy line of Android devices, it wouldn't be surprising to see Samsung drop WP7. Not to mention, there have been rumors that Samsung's hire of Cyanogen founder Steve Kondik was not a move made for his expertise in Android, but rather his expertise in Linux. The idea is that Samsung is going to create a Linux-based version of bada for release in the US, while keeping the current version of bada roaming the rest of the globe.
We're not sure what exactly the truth is, but it's certain that Samsung is putting a lot of effort into software, and likely wants its own software platform alongside its Android offerings. So, unless WP7 explodes in popularity, we certainly wouldn't be surprised to see this rumor come true, and see Samsung drop WP7.