In an article I read in a magazine, (remember those?)called Information Week this week they discuss a Cloud company that is folding. Coghead.
Won't bore you with the details but a new business will be popping up from Binary Tree probably any day now announcing how to migrate from Gmail.
Anyway, Google pricing in the article is interesting:
With Google's first-time payment structure for the previously free-with-quotas Google App Engine, customers pay 10 cents per CPU core hour, 10 cents per gigabyte of traffic in, 12 cents per gigabyte of traffic out, 15 cents per gigabyte of data stored per month, and $1 per 10,000 e-mails sent.
EDITED to just say
Once you let someone or something else manage for you it will cost you in the long run, maybe not today or tomorrow but....