As far as official positions go, I'm pretty sure that IHQ doesn't have a specific person that goes through every chapter website to make sure that it's in keeping in accordance with the best interest of the Fraternity. Still, that's why we have to put the disclaimer somewhere on the main page clearly stating that contents do not officially reflect the views and opinions of the Fraternity.
I don't even really see it as campus Panhellenic's responsbility either.
I think as members/officers/advisors we're really the ones who should be held responsible and accountable for the content of our chapter sites. I don't really see a need for anyone to be "policing" the sites since we all should have a good knowledge of appropriate and inappropriate. Basically, if you think a picture might raise an eyebrow or two and it might be questionable, your best bet would be not to post it.
While there isn't anyone "officially" regulating the websites, remember that we have IHQ/VST/International Council sisters who go online frequently. If they find something in poor taste that's somehow related to the Fraternity, rest assured that the involved party will be contacted ASAP.
This isn't just limited to chapter sites either. This also goes for personal websites, LiveJournals, GREEKCHAT! etc. -- ANYTHING that might contain the Alpha Gamma Delta name.
And there are a lot of big squirrels visiting these sites. Trust me.