Rush on Caspian Borders looked good actually. Conquest mode (where your team captures and tries to hold flags) is a different style of play that is certainly slower and less definitive than rush.
I can see what kind of player you are and you obviously like your action fast. Battlefield isn't like that really. Check out mrnelster's video links (one and two) and you'll see the first video you linked to is just a montage of moments from the developers play through, they've been lifted straight out of those lengthier (and slower!) play throughs.
The Metro map was infantry only and would have produced a far lower server load than the massive (up to) 64 player maps like Caspian Borders. I can see DICE's thinking and it is a shame they didn't make Caspian Borders available from the offset but had they, then hardly anyone would have played the infantry only map to the likely detriment of what DICE were trying to figure out by releasing it for play testing.
I actually enjoyed the Metro map but not so initially. It's a good map for what it is. Actually, it's a really good map with plenty of varied sections requiring some different tactics. It likely wouldn't play well in anything but rush mode though.
The park section was in one of the trailers a while back and featured an APC. I remember commenting on how poor it looked graphically and somebody mentioned the video made it look worse owing to too much compression. So we might see a different form of the Metro map with vehicles upon release. Or I might be mistaken as it might've been another park someplace like the one in NYC?
Anyhow, tick tock tick tock. No beta to play now that I have a bit of time on my hands and a few weeks to wait to get my fill of Battlefield 3 again.
Come on T2D! Get into the Battlefield spirit and um, take some tranquilisers or something to slow yourself down and learn to love having to run for miles as infantry in order to get to the heat of the battle and being repeatedly spawn killed over and over again and pwnd by jets and attack choppers. So much suffering in being a Battlefield fan - I hope you know what you're doing! My words will come back to haunt you for sure if you're not prepared to put in a lot of graft and patience!
Regarding the video you linked to in this post: at 3 mins 20. That helo player's flying skills are really good and it's just the beta he's playing. Not one single player whilst I was on Caspian Borders could fly the helos for more than 2 minutes without hitting the dirt rotors first so it's amazing to see someone with such control so soon. There will be something of a scramble for new players to master the art of flying the jets and helos as, as with the punctuated equilibrium model of evolution, there is so much at stake for people to make a name for themselves in on the battlefield as they each race to become 1337 players and get their names up the leaderboards. The [censored]!