Wow, this looks great. I looked at using Salesforce, and it was so painful (I've used it before) that we ended up just using RT (which is great for support issues, but sucks for sales).
Going to try this out for sales.
Also, yay for using Plivo and good call quality instead of Twilio. This should presumably support native SIP endpoints (and G.722), so I'm a lot more likely to use it.