Mobile OS phone operating systems

You're wrong and determined to be so.

Symbian is still active - Nokia 808 Pureview
Meego is still active - Nokia N9 is getting its latest update right now
Web OS is possibly making a comeback in 2013
Firefox OS is brand new, and will be in the marketplace in months.

Of the rest, only Bada and Maemo have been shelved.

Symbian is dead, the 808 is the final product on it.

Meego is dead, the N9 is just getting in market updates. Quite why is hard to fathom.

Web OS is dead. No-one wants it.

Firefox OS is likely to go the same way.