Mint.com still seems focused on the consumer market. They just released a new "Goals" feature which helps you reach your financial goals (like buying a car, a home, etc).
Just like with the rest of Mint.com, the Goal concept could carry over for businesses as well. Businesses have goals too. Plus, with the Intuit hookup, having automated bill pay, payroll, etc tied in is pretty sweet.
I meant, why hasn't mint expanded to SaaS for small businesses. It's a hugely under served market and they have a product that (seemingly) easily maps. Especially since they were bought by intuit.
All that being said I will likely end up using indinero. I've been waiting for this sort of functionality to show up somewhere. I think all of us business owners can agree quickbooks, excel, etc are all painful and antiquated.
My current solution is mint/tags + python script. And I much prefer it to previous experiences with quickbooks or excel.