I've just released a new version of Billr (2.2.0) which is a lot more stable, and we're working on the next version which is to include an API, cPanel and SolusVM integration (2.3.0). This should be out in about 2 weeks. I think the integrations will take another release to get perfect (2.4.0), but they should be generally functional in about 2 weeks.
I have two questions for everyone really.
1. What would you pay for a fairly simple piece of software that can do hosting billing with cPanel and SolusVM (you get the full source code) (version 2.3.0)
2. At the moment it just does Paypal and offline payments. I'm looking at integrating other gateways as well. Which gateways do you really want/need? The top 3-4 will likely be added in 2.4.0. I'm thinking 2CO, Google and Stripe so far.
I can see a lot of people are looking for a solid alternative to WHMCS and HostBill and I'd like to step up to the plate now that the fundamentals are there and there has been some testing with positive feedback, though of course it will be a case of small steps at a time.
James