Who is winning?
From how I like to play I'd say Jack is, but only slightly. He's got much better Pawn development at this point in the game. But since I'm not on his team...
What do people think of Bd5? It forces the exchange on a square that's less advantageous to Jack, the downside being that he has the option of exchanging Bishop for Bishop or Knight for Bishop.
Bxe6 is an even piece exchange, but it helps Jack take control of the center.
The other options I see are retreating the Bishop (d3, e3). This saves the piece for now, but you're worse positionally. I'm not seeing anything else great.
That said I tend not to see more than a couple moves ahead so I could easily be missing something.
(Oh and here's the text that's easy to paste into PGN viewer as the game stands.)
1. e4 c5
2. Nf3 d6
3. d4 cxd4
4. Nxd4 Nf6
5. Nc3 a6
6. Be3 e5
7. Nf3 Be7
8. Bc4 O-O
9. O-O Be6
10. Qe2 b5
11.