A few asked about the search engine approach we implemented on tradebit, here is the story:
We tried to keep the whole application search engine friendly. At some places you will still find parts that can be improved, but at least for Google we tried to be as friendly as possible.
the URLs to the files we host are completly without parameters, the parameters are part of the URL. The names you choose in the member area for your files is put into the title and the detail pages should rank fairly good.
The users get a subdomain they can use to link and gather their pagerank into their own world.
Navigation and grouping is done text-based or with "alt" tags, if pictures were choosen.
All in all, tradebit should be SE friendly by default and we are NOT evil ;-), no hidden links, no keyword stuffing, no bad neighbourhood, etc.
For the SEOs among you it should be a nice B+ and we are heading to the A...
cheers,
puzzler
