Has the Sicilian become a little unfashionable?

Especially at very top level.

In game explorer here, there are more than twice as many 1. ... c5 as 1 ...e5. But there are very few lately in top tournaments, why would that be?

Just an aside: In Tartakower's 500 Master games, there are only 16 Sicilians out of 500 games. So, it came from nowwhere, Dominated the last half of the 20th century, and now seems to be fading.......

I guess computer analysis is killing sicilian variations quicker than other 1.e4 defences.

Interesting, because didn't Fischer say the Sicilian was the best defense against e4?

I think you'll find that it's simply because today's top players were born with very small testicles. Once nature corrects this abberation, normal service will be resumed.

ROFL Doggy..Well said :)..

Another example is the matces betweeen carlsen and anand, no sicilian yet ! But I think that because of the sicilian's popularity, every day more lines are being found and if you don't know the latest theory you may let your opponent to take an early advantage (I am speaking about high level)

Perhaps because it is so commonly known that people are trying to veer away from it in hopes of surprising their opponent's plan? I mean, after all, if you play a strategy so widely known and your opponent has played it enough as well, wouldn't you just be playing it move for move into a stalemate without much room for creativity?

The Sicilian avoids dull symmetry that white has the power to bring to the table if 1.e4,e5 2.Nf3,Nc6 (or 2...Nf6 if you're a douche) 3.Nc3 and 3...Nf6 is the only viable move, though 3...g6, while not correct, is my preference as it desperately tries breaking the symmetry. 

1...e5 is stronger and more principled.

Why does Nf6 make you a douche? Oh, and I like your username 

Doggy_Style is correct.  Essentially, most of the current super-GM's are just pussies.  There are a few exceptions, Nakamura, Grischuk, Gelfand, Svidler. The rest just play "not to lose".  

Too easy to avoid at the club level - many anti-Sicilians.

I think that we could agree that there is no such things as a "best move against e4". Or against any first move that white may play. Or any best first move for white for that matter. 
There are only worse first moves. 

Anti-Sicilians aren't strong variations, all Sicilian players know that 2.Nf3 and 3.d4 is the most worrisome direction that White can take the game(for the 2nd player).  People who play e4 and think anti-Sicilians are actually "anti-Sicilian" are misguided and are just too lazy to learn theory.  

Play D4!!! 

Because the Petroff is infamous for lacking imbalances usually and has a very drawish reputation. 

And thanks ^_^

Most anti-Sicilians are weak, but some are actually ok.

In fact, the 3 Bb5 one is now very popular in both club and GM level and is scoring decently for White.

But with the drawish reputation wouldn't that be benificial if you NEED to create a draw in a match setting? Or are you stating that it's a sissy way to play?

2.c3 and 2.f4 are weak, but the Kopec variation and 2.Nc3 are wonderful alternatives for those who wish to avoid open Sicilian theory.  2.b3 is a joke that's ironically weaker than 2.b4, though 2.b4,cxb4 3.a3,d5! black already equalized. 

I think the Kopec is kinda dubious, but that's personal opinion.  I wholeheartedly disagree with your idea that 2.b3 is weaker than 2.b4...I think 2.b4 is the worst second move for White!