Hi Jennifer,
I'm curious to know which users you surveyed. There are a handful of people at the old p2p.wrox.com forums who pretty much answered 75% of the questions that came through on particular lists (Imar Spaanjaars, Jeff Mason etc). I did a quick search through my Sent-Items folder, and I put through 2731 messages (all answers) since the beginning of 2002 alone.
Whilst you may attract plenty of posters using this web-based system, the people who answer lots of questions are probably not willing to spend a lot of time on a web-based forum. I know that I'm not willing visit multiple websites every day to check to see who might need help.
With an list-server based solution, I can get all my ASPAdvice.com, 15seconds.com, P2P, Evolt, Developmentor, MS Newsgroups etc mail/news in the one client, and can quickly scan (using the one program) all the incoming queries, and reply.
I realise that you have various concerns about email-address harvesting, spam etc, but most commercial list-server products address these problems (Lyris, Listserv etc). I realise, of course, that they aren't cheap either. :-) The email-address harvesting problem, in particular, was something that was a product of the old P2P team's custom-built archiving system, rather than a problem with Lyris (which has its own, rather clunky, archive).
To end, I realise that you have any number of competing priorities (time-to-market, cost, usability, return-on-investment), however as one of the original subscribers who's been with P2P all the way since it started, I'd really urge the new P2P team to consider returning the previous format.
Cheers
Ken
http://www.adOpenStatic.com/
PS: And to consider giving/donating books to frequent posters. I received a fair few in the early days before Wrox started having problems. It helps breed loyalty to P2P, and it also helps answer questions where the poster refers to some code on a page in a book that I'd never consider buying. :-)