Did anybody else think the ending sucked? I guess it's supposed to be a setup for Earth 2170.

Ye. Ending is a bit disappointing... But overall its an awesome game :D
For now there is no info about E2170.

I haven't finished it yet, but to be honest whilst 2140 and 2150 were games very much built around single player 2160 feels much more built around multiplayer to me - the singleplayer campaigns were poorly voice acted, even more poorly scripted and generally felt very much like it was tacked onto the game so its no surprise to me that the ending is rather poor.
Hopefully the games MP (which is rather good I feel) will have given it enough sales and fans to warrent the company revisiting the series to make another game

Personally, I have no interest in multiplayer. I simply don't have the time or inclination for it. I thought the single player campaign was quite well done. The voice acting isn't great and it falls out of sync in the cut scenes (but is this a problem of translation to English?), but I didn't think there was anything wrong with the scripting. There is one LC mission with a badly placed laser wall that eventually blows up part of your base(!) which was rather annoying, but once you remove the offending wall, it works fine.

Well by scripting I more meant the actual story and words that the actors played out - it just lacked any depth to it. I guess with better voice acting it could have made all the difference, but if your not going to have 1strate actors then at least have a 1strate story to keep things going.
I do agree with you though that the actual computer scripting and coding appears solid - and the cut scenes do show quite a bit of work with the games engine (shame we never (far as I know) got to play with a copy for playcreated maps and stuff)