I think the graphic your referering to, topcomposer, is the one stating that the 2.0 version was released last July. I received an email from them a few weeks ago stating that they were waiting for the results of beta testing to determine a release date.
I spent a good deal of money last month buying a new G4 with the sole purpose of using it with Altiverb. I found out the hard way that new G4s will only run OS X. I tried every trick I could think of, but there seems to be somthing, perhaps in the firmware, that is able to prevent boot-up from a valid OS 9 system disc (CD or hard drive.) So I have an expensive paper weight with an apple logo on it now.
I write this as a warning to others out there. There were no clear warnings from the Apple vendor about this, nor was it very obvious on the audio ease site that Altiverb did not support OS X. Several audio engineer friends of mine were planning to buy a new G4 soon, but they are steering clear now.