Heroku dev status: Git push and API access have been temporarily disabled
status.heroku.com
status.heroku.com
If you tried to write a few scripts to automatically deploy your code on N instances, manage http load balancing and all the nice but invisible features of Heroku, I'm sure you would be down more often than they are ;-)
My dedicated server did go down today. I guess that's what I get for starting this comment thread.