I think sharing how many partners and what kinds of acts, in general, is fine as long as both partners are comfortable sharing. If someone isn't comfortable i think they're obligated to disclose that they have, in fact, had sex and if there are any related issues that would affect their partner. I can't imagine tallying it up like these folks seem to have done "Okay how many times did you do X with Joe? And Fred?"
My main issue with the LW was that he rejected his wife's offer to do something because he assumed she didn't like it, then, when he found out she did like it, he complained that she'd done it more times with old boyfriends than with him. Well duh, you turned her down when she tried with you! The poor lady can't win!