Yes, they have added all sorts of new features, even more announced this week. I’m still unimpressed. Until Pownce has a public API, and a way to use it with a mobile device built on that API, I’m simply not interested. All the rest of this stuff is pure fluff until that exists. The service is simply unusable as it is.
By comparison, I can use Twitter from my blackberry device, and communicate with my “friends” wherever I am. I don’t have to go to the website, nor open another desktop application to use the service. It integrates with Gtalk, and I use it anywhere I have access to Gtalk. That simple feature makes it 200% more usable than Pownce, regardless of all these features.