Is Google App Engine a worthy platform for a Lifestreaming app?
Pulling feeds or doing calculations won't be a problem. But  you'll soon have to pay for your account. App engine includes Django, except you'll need to work with some adaptors for the model part. It will surely save you from maintenance headaches.
I'm building a Lifestreaming app that will involve pulling down lots of feeds for lots of users, and performing data-mining, and machine learning algorithms on the results. GAE's load balanced and scalable hosting sounds like a good fit for a system that could eventually be moving around a LOT of data, but it's lack of cron jobs is a nuisance. Would I be better off using Django on a co-loc and dealing with my own DB scaling?