I'm a confirmed photoSIG member (since Jan/03) so have seen it's ups & downs. The good news is there; s a new admin who is not so confrontational & has plans to improve the site through member involvement. Robert has some vision for the site & is polite but firm. I think his influence might result in a new flowering for the site & photoSIG is the only photography site I'm aware of where you're likely to get a decent, helpful critique of your photo instead of Flickr fluff. You mightn't always like the crit but that's good, it makes you think critically about the points raised. Of course not all crits are great, far from it, but there are some good photographers & critics on the site who really put in.
I had my run ins with Sheena but in her defense I would say some of the people she dealt with were impossible. On the other hand she did seem to pick fights & could be somewhat undiplomatic but she put her heart into the site.
If you want critical reviews of your work then photoSIG is the place to be. It's worth noting there is an expectation that for each photo you submit to the site you're expected to do 3 crits which is a great way of improving your photography skills.
Would I recommend the site? Yes,
EDIT. Sadly the site went down in the middle of December 2014 & hasn't been rebooted by the owner in over 2 months so I would say photoSIG is now dead.