On a practical note
I have been through this re-branding process a few times before professionally, so if I may offer?
I think it would be very useful to set all the logo concepts at the same scale, on the same background and number them. Then you can make a fair comparison and consider how suitable and attractive they are for the site context. Which ones work and stand out - and which ones don't.
One point to consider is that all good logos (including all the global brands) work in black as well as colour. Because at some point you might need to photocopy, embroider, stamp, etch or screenprint the logo in a single colour, maybe very small - and still recognise it. The simplest are often the best.
A gallery would rekindle interest in the competition and attract more ideas from new people too. There might be some good ones that are nearly there, but just need an obvious tweak to make them better. Once they are all in, you could close entries and take a poll...
Free beer tomorrow?
A small incentive/prize would get this project a lot more attention and response too. After all it takes time, knowledge and goodwill to design and produce good work. Some have already spent a long time on their ideas, but it helps others to justify the effort. Just an idea.
Then when someone up there has judged and you have a winner, the logo may need to be professionally created ready for web, email, and anything else you might need (printed etc). The chosen concept will probably get tidied up at this point.
Best of luck!