An application written in any language manages tile updates using the WinRT API, so there is no difference in capabilities from this point of view. Updating a tile that creates a living tile is a simple XML fragment that you send to the TileUpdater.Update method, and samples such as Sample plates and application icons , Sample secondary fragments, and Sample Push and Periodic Notifications show all theme options.
On the server side - to create a periodic notification service or for those who can issue push notifications - you can pretty much use any server language you need, like PHP, ASP.NET, etc., since it is just a question creating XML payload for fragments.
Chapter 13 of my recently released book Programming Windows 8 Applications with HTML, CSS, and JavaScript . The e-book is free, so there is no excuse not to download it :)
.Kraig