No grandmasters, and very few IMs play the Baltic these days. The refutation line is given in many popular books, including Modern Chess Openings, Nunn's Chess Openings, and Informator. Some of them call the opening the QG Refused. I haven't seen the book you are referring to, but I would be surprised if it has changed the evaluation of the opening.
It could have surprise value, but if your opponent knows the theory you are in for a very inferior position.
On the other hand, Morozevich has shown the Chigorin to be a playable modern opening.
As I mentioned in the thread about the Albin CounterGambit, I was looking for something new to play against 1. d4, so I bought the book "Unusual Queen's Gambit Declined" by Chris Ward for info on the Albin. But besides the Albin, that book also covers the Baltic and Chigorin, and in looking through it, I've decided that the Baltic (1. d4 d5 2. c4 Bf5) appeals to me the most of the three. I'm not really sure why - just a gut instinct.
The fact that 2. ... Bf5 messes up Colle players as well as working against the QGD is a plus. And people who delay c4 by playing 2. Nf3 first don't avoid it. Actually, the only way I can think of for white to really avoid it after 1. d4 d5 is if they go the Blackmar-Diemer Gambit route and play 2. e4. I've played the BDG enough as white to know how to deal with it, so that doesn't really worry me. Or I could always go with 2. ... e6 in that scenario and get the French, which is my usual response to 1. e4.
I've been mostly focused on endgame study lately, so I haven't had time to read the whole three chapters in the book on this opening, but I have skimmed them a bit and played over some of the games. I've also tried the opening twice myself so far in online games and enjoyed playing it, even though I didn't play it perfectly. At least I got interesting games.
Does anyone here play the Baltic? Anyone have any recommendations or warnings for traps or lines I should know? Anyone know of any interesting games to look at in this opening? Any variations that white can use to avoid it besides 2. e4?
Besides that, is this opening considered sound? I know it's named after Keres, but I was wondering if any grandmasters play it today. Not that I would refuse to play an opening if it's unsound (I do play the Englund Gambit and Blackmar-Diemer Gambit, after all), but I'm just curious.
--Fromper