I have an application that polls several rss sources on the web.
What is the etiquette when polling other\'s web servers. How frequently to poll, etc?
What a
This is not a complete answer, but look for push alerts.
The RSS blog indicates that a best practice is asking weblogs.com about changed blogs.
There is also some, er, hubbub, about pubsub, a way to subscribe to push alerts that has some momentum.