It's only available to install as a set of DVDs, but anyone who preordered probably has received them by now. I installed it yesterday and it took literally hours to install the entire world. It also contains worldwide bathymetry for P3d only. The mesh is definitely more detailed in mountainous areas and has improved substantially outside North America. Within NA, one will see some improvements over the previous version (FS Global 2010). There are some local meshes for western NA mountains  (Shasta, Diablo, Rainier, Hood, St. Helens for example) that are pretty detailed. Be forewarned though, there may be additional elevation issues with airports that were not seen previously. So far I haven't seen any, but the guys at ORBX are not yet claiming compatibility with FS Global Ultimate.

 

So far, I don't see any impact on either VAS or performance, but I can't say that I have done any "scientific" tests.

Not really sure the price/benefit ratio is really there.  Does the high cost really gain a simmer that much of an increase in realism?

Offhand, for anyone just flying NA, I'd say no it doesn't. But if one does a lot of flying in Asia, South America and Africa, the improvement might be worth it.