Well, people are still discussing shows off the air for decades here.
After the end of ENT I started getting into Trek Lit and fan fiction so I mostly frequented those forums, also General Trek and TNZ.
But discussions about a possible new film began pretty early on if I remember correctly. Funnily enough because right after ENT's cancellation a lot of people thought there wouldn't be any new Trek for quite a while (Someone coined the phrase "Computer: end franchise" in mockery of one of the last lines in ENT's final episode). As a matter of fact that was also a popular line of discussion: how and when to revive the franchise.
After the end of ENT I started getting into Trek Lit and fan fiction so I mostly frequented those forums, also General Trek and TNZ.
But discussions about a possible new film began pretty early on if I remember correctly. Funnily enough because right after ENT's cancellation a lot of people thought there wouldn't be any new Trek for quite a while (Someone coined the phrase "Computer: end franchise" in mockery of one of the last lines in ENT's final episode). As a matter of fact that was also a popular line of discussion: how and when to revive the franchise.