- Web forums can be indexed by Google and hence show up in search results
- Web forum sysops can easily decorate a forum as they please, creating a little more personality than an average mailing list
- Forums often have fine controls in how posts as seen to the outside world
- Forums are easier to moderate - UI in place for banning IPs etc.
- Forums generally have a better community feel
- Generally have DB backend, making it easier to do queries to see how many posts a certain user has made etc.
- Instant gratification - you can confirm your post is live
Mailing list problems:
- Hard to subscribe
- Sometimes difficult to confirm your post actually was posted
- Cliquey atmosphere
- Often no public archives or poor Web archives
If you're a fan like myself of email, please consider taking up a project to write a decent mailing list Web archive system.