TGP2 is a neat idea, the problem is a total lack of standards. I mean sure, they have them, but there is no standard standard. There are rules, but I'd go far from calling any of them standard.
I think there are only 2 things that matter in making a free site work.
1. Understand the nature of your niche.
www.mature-post.com and voyeurweb have done great at this along with others.
2. Learn traffic. Big numbers mean shit. Focus on getting it right, and growing steady. There is no magic charm.
In TGPs, I can basically bet that a gallery that has...
16 thumbs linked to 16 pics
Pics over 20kb in size
Proper Recip
Paid Hosting
No Cheating
No Javascript
1 banner
1 textlink
and 70% content
Will get list at 97% of all TGPs... I cannot say the same about TGP2, or at least I haven't been able to find it. And EVERYONE needs to close their circles a bit. Open signup forms are a formal invitation to be hit botted.
TarPy