Mongoose Publishing is putting out their flavor of Traveller, which is mostly CT, with a slightly improved characgter generation and task system. I have the basic book, as well as their Mercenary and High Guard editions. I wasn't that impressed, but I'm told the quality of writing really did get better after those.
T5: Marc Miller's Fifth Edition of Traveller. The core rule book is massive! It was published as a Kickstarter project. It raised record breaking amounts of money for an RPG project, and you certainly got your money's worth with that giant book.
Classic Traveller:
Marc Miller produced the trilogy of Traveller. Three small black books, or
one big one, depending on when in the 70's or 80's you bought it. The rules
were simple, the action fast. The Imperium was big and intact. The Zhodani were
the bad guys, the Vargr were chaotic, and computers were big.
Of course it wasn't that really that simple. Serious Traveller players used Book 4, Book 5, and Book 6, at least. They also used JTAS articles, and the nifty stuff from Paranoia Press.
Classic Traveller is available in Big Floppy Book format or as searchable PDF files..
MegaTraveller:
In the mid 80's came a new version of Traveller. Several 8.5x11" books with
brightly colored covers. The rules were deemed good, once you had all the
errata. The design rules were complex, but allowed construction of fusion
powered roller skates to star ships. That is, once you knew were the bugs
were.
MT also brought the death of the Emperor and the start of the Rebellion.
Many embraced the change. Others clung to the days of a stable Imperium.
Some fled the Errata beast of MT. Many fled their Traveller, others invoked
the rules of GURPS to maintain their Campaigns.
Traveller:The New Era:
Traveller under GDW's House Rules. Major changes to mechanics and the setting.
The Imperium collapsed (but a Flame still burns in the Spinward Marches)
under the weight of the Rebellion and the VIRUS. Many use the new
rules, but a CT setting. This disappeared when GDW went
out of business.
Traveller, Mod IV
With
GDW
ceasing to do business, Traveller rights rights have reverted back to the
orginal author, Marc Miller. T4 (as in the 4th rev of Traveller) is out.
It's based on the CT rules. It's also know as
Marc Miller's Traveller. The big change is the setting.
The time is Year 0 of the Third Imperium.
This was published by Imperium Games.
Imperium Games dropped it's support of the Traveller line due to bad
investments overseas.
Marc Miller pulled their license to publish Traveller material, in part due
to books that made MegaTraveller look errata free. D20 Traveller: T20
Traveller based on the D20 rule set. So yes, you can be a 5th level Imperial
Marine/2nd level Noble. A concept which deeply troubled many old time
Traveller players. Didn't bother me too much. Ran a T20 PBEM for
years. Mongoose Traveller: RTT
Mongoose Publishing's take CT, with a slick character generation upgrade and
a simplified task system. Traveller Fifth Edition: T5
Marc Miller, after years of tweaking; finally released his Traveller
Opus as a Kickstarter project.