Github is also very vulnerable on price if you have the need for a lot of small, private repos. If Amazon charges on storage (like they do with S3) instead of the number of repos, it will make this a compelling alternative for a lot of businesses.
Leaving the conversation about small plans aside, we can set up a plan for you that has as many private repositories as you need. Just email sales@github.com and we can get it set up for you.
The only thing that Bitbucket devs wont add is gist :(
Something like http://aws.amazon.com/s3/pricing/ combo of storage + requests