So THAT'S why fantasy is #1...

[Xeriar]

Cyberpunk 2020 is one of the ultimate examples of dated RPGs.

Transhuman Space was interesting, but I found it ignored a lot of problems that China and the EU would be facing over the next century and (comparitively) ignored India altogether.

It's hard to make Sci Fi that won't date. Books like 'The Moon is a Harsh Mistress' and 'Starship Troopers' are more there for the lesson they can provide (in my view anyway.)

Captain Picard stating 'Like Fermat's last theorum, there are some things that we may never solve.' is an example of sci-fi asking for it. (Proven that year or the next, I forget).

Semi-modern settings get to rival Fantasy's dominance because Earth, being the most detailed setting the human race has, provides a great deal of source material

Shadowrun, CoC and the World of Darkness are still quite popular.

 

[Dogbrain]

Right now Transhuman Space is representative of the latest sci-fi themes, but will anyone still take Transhuman Space seriously in 10 years?

Transhuman Space? That is, like, SO before last year!

Imagine if TSR had created a "Modern" RPG in the mid 80's.

It was called "Top Secret: SI". Yes, it is dated.

3. Long term campaigns don't work very well outside the fantasy genre. I suppose the best reason for this, as was mentioned, is that in some of the other genres there's only so far you can progress before you defeat the entire purpose of the genre (Uber powerful horror PCs???).

That's a limitation of scope. The problem is that a lot of other genres have permitted themselves to become small--PCs are always big, it's the genres that got small. Were a campaign to be set in Asimov's Foundation setting, at pretty much any part of the timeline, there would be room for as much "progress" as in any fantasy campaign. Of course, part of the "progress" problem is an artifact of the D20 system. This is probably why non-fantasy is dominated by game rules that do not insist upon such extreme, severe, monumental, and very very large gains in personal ability.