I am new video streaming programming although I have been doing entprise software programming for 10+ years, just to give you context. I am looking for feedback on my archicture and platform choices. Here is what I am trying to achieve:

1) web based SaaS application which will be mostly used on desktops and laptops(non mobile, non tablet consumers for now). This is an enterprise application.
2) The application page on client side will show streams anywhere from 1 up to 10 webcams. Most of the streams or chat will inactive so I am thinking that I can broadcast those inactive streams at a very very low frame rate untill they get activated by an user. So itīs many to many webcam streaming/chat.
3) In future I may have some mobile consumers with limited functionality.

I looked at html5 for the client side but very soon realized itīs not ready yet especially for device/webcam support and enterprise constomers will take a while before they upgrade to IE 9 etc.

Here is what I am thinking in terms of platform/tools:

1) client side: Use flash plus html. Or will be it better to entirely use flash. I do have other apps on the client side but I didn't mention them here since they are not related to video.

2) Server side: I am leaning towards wowza media server over adobe FMS to save cost. Any other recommendations? This is an enterprise application so security and robustness is very important.

Thanks.