I don't think it's as big of a deal as everyone thinks it would be.  I mean, when you start dating someone new, you don't compare every little intimate detail of their anatomy to every other person you've ever dated.  I mean, you might notice if anything was remarkably different (or unfortunately lacking! 

 ) but you wouldn't do a mental checklist of every little (or big! 

 ) thing.  
In some ways it might even be more comfortable to date a gyn - any insecurities you may have about your body, you KNOW he's seen way freakier stuff than you will ever get.  
One of my friends dated a gyn resident and she gave him extremely good reviews.  She said he taught her stuff about her anatomy that she didn't even know.  Sounds fun to me.