So I'm not working on this but I'm working on software that might be the base for this? An Open Source collaborative wiki calendar http://ican.openacalendar.org/
As others have said, data is the main problem. Sometimes it might be best to focus on a small area or niche. There are lots of sites like this but the ones that succeed generally seem to cover one area or niche (or both)?
As others have said, data is the main problem. Sometimes it might be best to focus on a small area or niche. There are lots of sites like this but the ones that succeed generally seem to cover one area or niche (or both)?