I believe it's due to a lot of changes I've been doing recently. Some of the changes I believe that have affected this are:
Updated user creation - Think this change has helped a lot. Before when creating a new account you would first verify the e-mail, would then send you a randomly generated password, you would have to enter that password, and then change it. Now you can simply enter your password in the user creation page and only have to verify the e-mail is a valid e-mail. I would like to get rid of that too, but as many know lots of trouble makers that would like me to do that... I know on my end this has helped TREMENDOUSLY because I was getting on average 3-12 e-mails from users being able to log in using the randomly generated password, since changed 4-5 days ago I've only got 1.
Opened up /CGI-BIN/ - In the past the robots.txt has blocked all search engines except Google (needed unblocked for CGI-BIN pages ads) from indexing the /CGI-BIN/ on Computer Hope. Of course since the forums are in the directory it too was blocked. This is now removed all search engines can now query Computer Hope and as can be seen from the stats yesterday 32 search bots were indexing the forums. Believe with forum results being found on other search engines this will also bring more entry points and users into the forums.
Promoting - Been promoting the forums a lot more recently.
I'd like to say it's also all the other minor updates and modifications I've been doing too, but don't think that's the case. I think the above three things are the biggest factors.
Finally, I think also more users are also realizing that the Computer Hope forums get a lot of questions answered very quickly and almost always with good answers, thanks to all the great dedicated Computer Hope forum members.