How often do you 'release" your web service to production?

We just launched our service and have got a lot of feedback from customers, which we are fixing daily.

I would like some feedback on the pros / cons of releasing bugs / new features as they happen VS. a preset schedule VS. release dates (V2.0 in April, V2.3 in June, etc.)

How often do you release your web application?

We are a subscription (paid) service BTW if that makes any difference.