I was very excited when GPO 4th edition was announced, and I await its release anxiously. Right now I own GPO 2nd edition, and I'll admit I was definitely surprised at the new "4th edition" as I was completely unaware that a 3rd edition even existed. I do consider myself pretty aware and up-to-date on the latest in available sound libraries, so I did find it odd that I hadn't heard of the 3rd edition before -- more so that Garritan never sent any promotional emails about it (at least I never got any). I did a ton of Googling and couldn't find any documentation whatsoever on exactly what the differences between the 2nd and 3rd editions are. More instruments? Better control?
Also, I fully intend to purchase GPO 4th edition when it comes out, and I know of the $50 upgrade, which is really awesome. However, I'm concerned about which versions of GPO qualify for the upgrade. Would it only apply to its predecessor -- the 3rd edition -- or is the upgrade available to users of the 2nd edition? I'll be honest, I would feel a bit cheated if the former is only true, considering the lack of information and promotion of GPO 3rd edition. I'd appreciate the help!