Yes it does. The only two shows that don't really have an acronym are Voyager and Enterprise. Otherwise the other 3 are regularly referred to as TOS, TNG and DS9
They all have acronyms, even the movies...
TOS = Star Trek
TNG = Star Trek: The Next Generation
DS9 = Star Trek: Deep Space Nine
VOY or VGR = Star Trek: Voyager
ENT or E = (Star Trek
Enterprise
TMP= Star Trek: The Motion Picture
TWOK or TWK = Star Trek (II): The Wrath of Kahn
TSFS or SFS = Star Trek III: The Search for Spock
TVH = Star Trek IV: The Voyage Home
TFF = Star Trek V: The Final Frontier
TUC = Star Trek VI: The Undiscovered Country
GEN = Star Trek: Generations
FC = Star Trek: First Contact
INS = Star Trek: Insurrection
NEM = Star Trek: Nemesis
As for them not being available, it is possible that they are having bandwidth problems, or their server is down, or they are updating with Season 2 and more of the re-mastered episodes.
As for them re-mastering the show, Michael Okuda is in charge, and he is making sure that the follow the spirit of the show, and don't pull a Lucas. The biggest things they have done is to use new CG footage of the Enterprise and planets, along with other ships. They are also working on fixing inaccuracies with the outside images of the ship, so there is more than those 7 stock shots. They are doing their best to enhance the existing show, not detract from the stories. The broadcasts of the show so far has been confined to the US and Canada (via US stations), but once all the episodes are finished, you can expect them all to be available on Television Worldwide, and on iTunes.
There is a hope that the same thing can slowly be done to the other shows, especially since they haven't done another film to video transfer for the shows since they were originally broadcast.
http://www.trekweb.com/ is a great source for more information and a forum to share you opinions about this, and Star Trek 11.
TEG