In his Play the French, 4th Edn, John Watson recommends:
[FEN ""]
[White "French Defense"]
[Black "Labourdonnais Variation"]
[Annotator "John Watson"]
1. e4 e6 2. f4 d5 3. e5 c5 4. Nf3 Nc6 5. c3 d4 6. d3 Nh6 $11 {M.Weiss-Maróczy, Budapest 1895. I think that Black's position is easier to play, and White doesn't seem to have a good way of making 2 f4 interesting.} *
Black's d-pawn is going to be hard to get rid of, and White's d-pawn is jammed behind it. Black aims for the natural (in the French) moves ...Nf5 and/or ...Qb6, and he's right at home, while White has trouble making progress.
I could only find about 60 games among players rated 2000 ELO or higher involving 2.f4 , so there's not much modern practical experience to go on, but the overall results were 22-25-13. So, it's certainly playable.
Needless to say, Nakamura's played it. He played it in the 2012 Sinquefield Cup, after having first run into it as Black in 2010 at the same tournament. I guess he liked what he saw. Other 2600+ ELO players who've tried it include Bologan, Zviagintsev, Stevic and Yudasin. It's most ardent supporter seems to have been the Moldovan Viktor Komliakov , whose score in games I can find was 4-7-2. But since he's now 56, he seems to be playing a lot less frequently. They might be a good reference, though.