The problem with supporting all frequency bands is not the availability of hardware to decode them, it's that consumers have gotten used to their nice thin devices.

Enough metal to wire up antennas even just for the (ridiculously long list of) bands used in the US would make the phone prohibitively thick.

You mean the Symbian that isn't open source yet? http://en.wikipedia.org/wiki/Symbian_OS#Open_source Steps in the right direction, sure. However Google has definitively beaten them to the punch on the actual open sourcing. Of course it doesn't particularly matter, since all phones are likely to be Tivoized for the foreseeable future.