Friends HD?!

So I’m flipping over to WGN tonight and they’re showing old episodes of Friends like usual…but now in HD!  And not like squish-o-vision like A&E does with their shows on the HD feed, but what appears to be fully restored and properly formatted episodes, even the ones from the first season.  I know Seinfeld got the redo treatment because it was originally shot on film and thus fairly easy to alter the aspect ratio, but Friends was done on videotape and only shot for 4×3.  Someone solve this mystery for me, and then give me a release date for the Blu-Rays!