A 'create your own vote' social media site.
Users can create a subdomain of (for example) comptwitition.com and create their own user-votable competition. The emphasis will be on inter-city/international competitions (my city has better manhole covers than yours, for instance)
When creating a competition, admin makes a competition rules page (choosing from a preset list of rules) an about page (premise of competition), chooses whether the competition is geographical or not and defines the level at which geographical competitions takes place (intercity/international/city street/etc).
If it is a geocomp, any image uploaded must be placed on a google map (or if it has LatLong EXIF, use that) and will then have the category (side in the competition) suggested. This should be overwriteable if necessary.
Images can be uploaded either directly via the site, via an iPhone app, having a flickr URL entered or a twitpic url entered. Entries can also be emailed or tweeted @comptwitition.
Votes are done via a tweet entered on the site. The tweet would be @comptwitition and include the user's vote and a shorturl to the entry page.