Nicely done, but there are few issues from the top of my head.
1. Security - this should really be going over SSL. In fact, the whole site needs to be SSL'd.
2. P2P - I bet you are not P2P, and you won't be able to be P2P if you keep the viewer in the confines of the browser. However, the client-to-client traffic really needs to go peer to peer. It's an absolute must. This is what keeps the cost of running the service low and this is what allowed LogMeIn to grow like a fire and eat Citrix lunch. You keep pushing all data through yourselves, your bandwidth usage and infrastructure upgrade bills will likely to kill you. Scaling a server-relayed service is a bitch of an issue, don't underestimate it.
3. Java dependency for sharing - you'd be surprised how many locked-down corporate setups have no Java (not that they are your target audience). I personally don't have Java installed either (and again, I am probably not your target user either). A fallback to Flash would make a lot of sense. Also the screen sharing on iPhone/Pad/etc would require a native app, which effectively means that you are on your way to replicate join.me.
4. Patents - I'm sure the easiest way to knock you down is through a patent litigation. Be mindful here. Try and build a bit of a defensive portfolio if you can.
All in all, good luck. You are entering a crowded market littered with failed startups... and interesting acquisitions ;)
2) We are currently not P2P but that is one direction that we are considering for a future complementary product. We have done some calculations and believe that it is possible to make service economically viable (even with free basic usage) but it remains to be seen if we are right.
3) Unfortunately, it is not possible to implement a sharing application purely in Flash because it does not provide the necessary calls as far as we know. Our goal is to remove the pain from viewing so an iPhone/iPad/Android version would fit in with our goals.
1. Security - this should really be going over SSL. In fact, the whole site needs to be SSL'd.
2. P2P - I bet you are not P2P, and you won't be able to be P2P if you keep the viewer in the confines of the browser. However, the client-to-client traffic really needs to go peer to peer. It's an absolute must. This is what keeps the cost of running the service low and this is what allowed LogMeIn to grow like a fire and eat Citrix lunch. You keep pushing all data through yourselves, your bandwidth usage and infrastructure upgrade bills will likely to kill you. Scaling a server-relayed service is a bitch of an issue, don't underestimate it.
3. Java dependency for sharing - you'd be surprised how many locked-down corporate setups have no Java (not that they are your target audience). I personally don't have Java installed either (and again, I am probably not your target user either). A fallback to Flash would make a lot of sense. Also the screen sharing on iPhone/Pad/etc would require a native app, which effectively means that you are on your way to replicate join.me.
4. Patents - I'm sure the easiest way to knock you down is through a patent litigation. Be mindful here. Try and build a bit of a defensive portfolio if you can.
All in all, good luck. You are entering a crowded market littered with failed startups... and interesting acquisitions ;)