Arduino DUE 3.3 volt question (vs Arduino Mega ADK)

Using Arduino Programming Questions
1

I am comparing 2 arduino mega's.
Both seam quite similar but the Due runs on 3.3 volt.

Does it mean that if i set a pin to high that it's voltage will be 3.3 volt ??, and is that enough for normal shields ? might some shields not work on it?

I am planning to use a mosfet shield to drive lots of leds

2

I am comparing 2 arduino mega's.

The DUE is not a Mega.

Does it mean that if i set a pin to high that it's voltage will be 3.3 volt ??

Either that or 567. 3.3 seems a lot more likely, though.

and is that enough for normal shields ?

Yes, if the shield is a 3.3V shield. There are shields that need 3,3V and there are shields that need 5.0 volts.

I am planning to use a mosfet shield to drive lots of leds

Which MOSFET? Does it trigger at 3.3V or 5V?

There are very few shields that connect to all the pins of a Mega or DUE.