Well, up until now Garritan's products have been primarily about {a} solo instruments and {b} building ensembles. They're just like any other MIDI VSTi plugins you may have, e.g., Coyote Forte, in that you assign instrument patches to MIDI channels, send MIDI signals to those channels, and the instruments play. And, yeah, you need a lot of notes, and possibly layered recordings, as most string VSTs simply aren't up to the task of pretending to be a whole string section.
GIO, on the other hand, has entire ensembles doing different things, rather than simply instrument patches. In other words, each patch represents a particular series of actions by a section of the orchestra -- e.g., the preset combo "Grand Cathedral" is defined as "Small orchestra and choir crossfading to full orchestra and a grand choir when the mod wheel is used." "Instant Gratification" is listed as "Full unison orchestra with more aggressive attacks." "Delicate Orchestra - Ethereal MW" is, literally, the sound of a delicate orchestra, with which ethereal (presumably pseudo-ambient) sounds are blended when the mod wheel is used. And so on.
Thus, the tedious ensemble-building part is already taken care of. Rather than try to figure out how to build what instruments up to the sound you want, you pick a patch and start playing. Layering presets in this case doesn't add instruments, it adds whole new orchestra sections with every note.
This thread at their online forum tells you where to get the complete list of patches and FX -- twenty-two pages of screenshots from the manual.
Here's a
nine-minute YouTube video that touches on some of what you can do. and in the Recommended column on that page you'll see a couple of short vids (less than 40 seconds each) by RobertDannyDavis showing off some instant play -- just picking a preset and going with it, no sequencing necessary.
The idea here is to make overall arranging much easier, and I can't wait to scratch up the cash for this. It's intended to supplement GPO (or any other solo-based orchestra VSTi), not replace it. And I can't help but think that, in a situation with this beastie as the default VST, PG or we or both can come up with some orchestra styles that will blow the world away. We won't even need to do anything really different -- just set the right patch, and it's already geared to handle the tricky parts.
The other great thing is that it's reasonably priced. There are other programs, such as Albion and Symphobia, which do much the same thing... but they range from about $500-550 to $1200. GIO is $149.98.
I hope I made sense here!
Can't help it, I'm just really excited by the existence of this.