Well, I guess it's time for me to say something again!

Khalifman only gives the four alternatives allready mentioned, eg 11)...Bxe3, 11)...b6, 11)...Be7 and 11)...Bb4.
After 11)...Bxe3 he sees white getting a clear advantage in all lines, but he doesn't mention 12) Qxe3 f6. Instead after 12)...b6 13)h4 he does mention 13)...f6 14) exf6 Nxf6 15) h5 b5 16) h6 g6 17) Be2 b4 18) Na4 e5 19) fxe5 Re8 20) Qc5 Ne5 21) Nb6 giving white the better game.
After 11)...b6 he is following Nijboer-Glek 2001, where 18)...Rxc6 instead of 18)...Bxc6 may have kept white's advantage to only +=.
After 11)...Be7 he gives Nijboer-Stellwagen 2002 with the amazing sacrifice of the knight at a4 after 19) Bd4!! This seems to be winning in all variations.
Finally after 11)...Bb4 he bases his recommended line again on games by Nijboer, eg Nijboer-Glek 2003 and Nijboer-Sielicki 2001. Most important however is his improvement on another game Nijboer-Stellwagen 2002, which went 12) Bd3 b5 13) g4 Nb6 14) Qf2 Nc4 150 Ne4 Be7 and now not 16) g5 which ended peacefully after 26 moves, but 16) Bc5!? He gives a lot of variations all leading to a clear advantage for white, except for 16)...Bxc5 17) Nexc5 Nb4 18) Kb1 a5 19) Rhe1 a4 20) Nd4 a3 21) b3 Nb2 22) Rd2 Qb6 23) Nf3 Ra7 24) c3 N2xd3 25) Nxd3 Qxf2 26) Nxf2 Nc6 27) Nd4 Nxd4 28) Rxd4 Rc7 29) Kc2 Bb7 30) Re3 Rfc8 31) g5! Kf8 32) h4 +=
I guess black has to search for an improvement somewhere in this line, but if there are any questions feel free to ask. Khalifman may have the answer!
By the way, this latter line clearly shows how much work these guys at Chess-stars put into their books. At critical points they readily give you improvements with a lot of analysis . I think this should be the standard for any book on openings!
I allso see that Semkov is actively having contact with readers of "The safest sicilian" via the Chesspublishing forum. That is great!