[fido]

Yes this does seem to be a popular choice. From a business standpoint, I like that the extra revenue flows in at the front end of the tier.

With this model, how will you do upgrades/downgrades? Would you prorate the portion of the month on the old plan + the prorated portion of the new plan? Then, continue charging on the new plan the following month?

[johnnytee]

I'm using Spreedly.com as my payment processor. They prorate and either credit or charge the account based on upgrade or downgrading. I've tried my own billing before it was a major pain in the ass.