I've heard that thunderbolt can be used as a displayport. That make me wonder if I can use two external monitors with mini displayport and thunderbolt to displayport or hdmi.
Is it possible??
The thunderbolt port and display port are the same port. So it's not two separate ports.
That said, due to the high bandwidth nature of thunderbolt, I suspect we will be able to daisy chain monitors in the future, as well as having thunderbolt "hubs" where multiple devices can be plugged in.
But for now, it's one port. So only one external monitor.
Thunderbolt can daisy-chain monitors, however the limits of the original system still apply. Mac systems with integrated graphics e.g. Intel HD 3000 can only run one external display. Those with dedicated 3D e.g. 15" Macbook Pro can run a couple of external Thunderbolt displays.