What is the real difference between this and the original MTW?

What is the Difference between this and the original MTW.What Factions are there?

I just played my first M2TW a few months ago and I haven't played MTW in over 10 years (can't get it to play on newer machines), so I'm probably not the best person to answer your question. However, I will get the ball rolling with a few obvious things.

1) The campaign map in M2TW is a 3D type map like in RTW as opposed to the Risk-style map of MTW. This means your armies can maneuver within provinces instead of just occupying the whole province. The terrain determines how far your armies can move, though there are roads (which can be upgraded) which can speed your armies along. When two armies clash, the battle map is generated based on the terrain where they meet.

2) In M2TW, provinces can have either a city or a castle. Castles are more military based, while cities are more for economy and technology.

3) There are fleets you can build and move around. You can use them to transport armies, blockade ports and fight the fleets of other factions. There is naval combat, but it is auto-resolve.

I'm sure there is more subtle difference, but like I said, I haven't been able to play MTW for a long, long time.