Watch the battles in the trailer, if you notice, some are in open space(open space I mean not rocks and clouds everywhere...) Does this mean they they realise that we want good open fights? Or is it just on some maps?

Well, if the map maker is ever released, that will solve the small space map problem. Plus, with the new bigger ships, you'd think the map would have to be a whole heck of a lot larger.

The maps look bigger in the trailer. Near the end of it there is a shot where you can see a player selecting an ISD. If you look at the mini-map on the left you'll notice how much larger it has become.

Edit: I made a screenshot of what I mean:
http://www.imagebucket.net/images/Palpatinedc/largemaps.jpg)

I just found an article at IGN.com that reveals alot more than any other article I've seen so far, along with some cool screen shots. Everyone should have a look at this: http://pc.ign.com/articles/707/707748p1.html) I'm not going into details, you MUST read it for yourself. This expansion is going to be really awesome.

There's even a screen shot of the SSD losing some hard points, resulting in the nose breaking off.

Points of interest: Larger maps, ground transports, and terrain that is only passable for infantry units.

That's indeed a very good article, but the sceens ING posted come straight from the LucasArts website. Still a very good find , because of the info in it.