Apologies for the OT - I tried playing the Sicilian in my younger days but was put off with:
1) the ridiculous number of people who played 2.Nc3/2.c3 - the former is easy to play for white, the latter changes the character of the game to a much more positional one. At my levels I almost never got an open sicilian.
2) the general style of play - I struggled to handle the Sveshnikov-type structures and have never been fully convinced by the Dragon. The quieter Scheveningen-style setups really didn't give me the type of game I was looking for... and again, since I got each type of position so rarely due to the number of anti-sicilians, I never found a comfortable fit.
3) the boredom factor - it seems everyone and their pet kitten plays the sicilian. I got so bored of facing it as white I switched to 1.d4. I like to play stuff which allows me scope to improvise or surprise. Needing to learn 25 moves of sharp dragon theory and keep up with the latest developments seems a lonely way to lead one's life. Much rather throw in a latvian and get a game of my own where my opponent and I both need to think.
I know there's a body of theory with the French also... but I'd imagine less is needed in order to confidently play it, most don't spend as long preparing for it as they do 1...e5/1...c5. And, as people have already posted, if people like Williams are attracted to the French, it clearly can be played ambitiously and aggressively. The number of ...g5 thrusts makes this quite obvious.
I'm led to believe that the Caro-Kann can be interesting and sharp... it is generally the stodgemonkeys that choose that opening that choose to make it dull. So it is with the French... there are several dull lines, but it seems much harder for white to choose a dull game? (Maybe the KIA setups are the way to do this, and the Tarrasch might be less sharp... but it's pretty much impossible to avoid some quieter variations)
Anyway, I have ordered both books, and look forward to trying to work out how to learn the opening. I've got to grow up and learn one eventually...