See http://chrishajer.com/bbpress/before-and-after.png
The descenders on letter P and letter Y are being cut off with the default CSS (left hand, Before image). I found that modifying the line height helped (the right hand After image.)
I didn't do a ton of testing with different browsers, and I know I can do other things with the CSS, but I would like to suggest that the default CSS have a line-height set that allows the descenders on p, q, y, g, Q, (etc.) to be properly displayed.
Thank you.