Yes, it is new. You may have the ARC MINI (the R2 version comes with a window) but so far the ARC MIDI R2 is only available with a tinted window. There are also other updates with the layout too. This should be cheaper than the windowed version but will probably launch at the same price, so around the £70 mark.
How about the mATX Define R4 gets a windowed version?
Seriously. I've been on the lookout for a windowed mini tower case and the Obsidian 350D seems to be the only one on the market. While the case certainly isn't bad, I would prefer a windowed version of the Define Mini because my current rig sounds like a jet plane,