So I would like to revive this, emphasising point #1 in the OP. Webcam/microphone access through JRiver's Chromium engine implementation would be really, really cool, but I wouldn't call it as essential a feature as a full-screen/maximisation mode for said browser, in both standard view and theatre view.
What this would effectively do is remove every issue y'all have ever had with integration with services with non-public API's, such as Hulu, Netflix, and YouTube, sans Gizmo-like swipe scrolling and input. All that any of us would have to do is define the appropriate web site links in the links bar and/or theatre view options; check a box that says, "Run browser in full-screen for this item"; and
boom! We now have service centralisation without you having to pay egregious licensing fees and sky-rocket the price of MC licences.
It helps that
www.youtube.com/tv exists. Currently, it can be added as a theatre view item, but theatre view doesn't maximise it for some reason. Netflix's web site look-and-feel is also appropriate enough for a ten-foot interface, albeit that you might need a remote that supports mouse input/emulation/whatever the proper term is. RealVNC Viewer on Android, running with access to RealVNC Server on the HTPC (assuming living room implementation without keyboard/mouse input of its own) is a good example.
Bonus points if the MC browser engines can save and retain cookies, so that one could remain logged in to YouTube TV when one closes and re-opens it.
Can this be done? I know that not everyone has an external remote software implementation, but I figure that if JRiver bothers to include support for DVD's and BD's unlocked via external DRM removal tools such as AnyDVD HD, it's certainly not unreasonable to say it could support web browser features that complement the use of said external remote software implementations.