Stripe is amazing for developers - and the CEO has been very accessible via Twitter.
Really straightforward API. Also affordable. From their site: - 2.9% + 30 cents per successful charge..
"Stripe handles everything, including storing cards, subscriptions, and direct payouts to your bank account."
For companies that have more serious (enterprise-level) recurring revenue, I recommend Vindicia (Vindicia.com)
They're fantastic for big data analytics around subscription revenue (optimizing revenue once your numbers are high enough.)
CEO, MakeOut Labs