@Bass: I think a common app ecosystem (at least across the *nix based devices (i.e. Android, Ubuntu, Firefox)) would be really good as it would lower the barrier to market entry for new OSes thus increasing competition while enabling ease of switching OS, reducing developer workload and widening the available number of apps on any given platform.

Sadly I've seen no sign that anyone's working on anything like this (excluding web apps) - I can understand that Google may be reluctant to join initially, but if Mozilla and Canonical could kick it off then over time it may grow big enough to force Google to come on board.

EDIT: Allowing web apps to make calls sounds like a recipe for all kinds of premium rate scams embedded in websites...