Thanks for the clarification and keep up the great work. So far I'm loving the improved accepted % of the new stratum mining protocol.
One thing that would be cool is if we could run just one mining proxy for multiple pools - ie if the mining proxy had some sort of config file or could bind to multiple ports on the machine running the software.
It would be cool, but it would be "pointless". poclbm now has native support, and cgminer is adding native support soon. Between these two mining clients, that's roughly 80% of the speed on most pools. Once the miners have native support, you can just run regular backup pools instead of the proxy, or use 'load balancing' in cgminer to split work among multiple pools.
The proxy is mostly a short-term solution to get the protocol out there and usable for old mining software. It may see some long term use though for large farms (more than 5 separate machines). The overhead on stratum is basically static per connection. So running 5 machines with 5 separate connections will use 5 times the data, whereas using a single proxy for 5 mining rigs uses the same as a single machine would (at least with dynamic difficulty adjustments).