It's not going to happen. (Picture from Full Tilt Poker.)
The only way it could happen is if Google decided all this talk about mobile computing is just mush, and not really worth pursuing. Then it might shove its code to the Swedes and just walk away.
But that's not a merger. That's a capitulation.
Despite the word phone being in its name there is a lot more i than phone in the iPhone.
Symbian is basically a Real Time Operating System (RTOS) dressed-up. It's a fine way to run a phone. It's no way to run an Internet terminal.
Thus to claim Symbian is going to "take over" the effort against Apple is to claim that Wind River's RTOS is better than Linux. Even Wind River knows better than that.
An Internet terminal needs a lot more functionality, and a completely different interface. The iPhone is an Internet terminal. Its users scarf up hundreds of times more data than users of any Symbian phone.
The whole aim of LiMo, Android and Symbian right now is to create an interface which will enable that same interaction.
All the present dancing tells us is none of these groups yet has an answer. They're all poker players bluffing with a pair of 3s.