Personally I think that usability is the most important factor in a webapp. I bet that most of the people here could code up the logic of a dating site, wikipedia or del.icio.us in a week or two - many webapps are pretty simple to code.
The difference between a good and a bad webapp lies in the interface. And interestingly the simpler it looks the harder it probably was to make.
The difference between a good and a bad webapp lies in the interface. And interestingly the simpler it looks the harder it probably was to make.