This is something right up my alley. While I rarely post them to Chief Delphi, I do my best at every event to photograph as many teams as I can. For one, photos can serve as a useful scouting tool. Also, as I've found, many teams lack quality photos of their robot for use on the web, promotional materials, etc.
I usually don't post to CD because of the amount of photos I take. However, they can always be found on my Flickr a couple days after the event (
here). I went to 5 regionals last year and championship to try and get pics. This year isn't as packed, but we'll see. I can't be everywhere, but I do what I can.
On my flickr, you can search tags as every photo has been tagged with the teams it contains. Searching frc## will pull up the teams (that is, no preceding 0s, thus 25 is frc25, etc).
It wouldn't necessarily be a bad idea to have a Flickr pool with the year's photos, that way you can search by tag and it won't overrun CD-Media.