How would ADDING support for 4th edition (ya know, their current edition) be a bad thing? It's obvious they are giving the middle finger to their current edition fans. The exact same crap happened at the end of 3rd edition with the release of the forgotten realms timeline (which was cool) and their Eberron adventurer's guide.
I'm all for editionless books but wizards ONLY does this when it suits them (ie . changing editions). They want to do everything in their power to get everyone to change to 5th edition by dropping support for their old editions. Honestly , i'm surprized that the character builder and compendium are still up . Wizards has a TERRIBLE PR philosophy, and it saddens me that some people don't understand this.