You won't find a better competitive FPS anywhere, period.
Battlefield 2142 is a great online FPS has three very distinct problems, which are actually not problems at all. First, it's not Battlefield 2. One of the most important points of criticism when dealing with this game has been that it looks like a simple mod for BF2. I, for one, disagree. It may use the same engine and gameplay, but the innovations are quite deep. Now, for instance, teamplay is greatly encouraged, so you will receive points for doing benefitial things for your team such as repairing or healing. Even more, you get extra points if you obey the orders of your squad leader. This little feature, that may seem unimportant, is actually a pivot of the entire gameplay. No more loose men running through the battlefield like headless chicken. If played with a good squad, the game ceases to be a game and becomes an experience, pure and uncut war. Seriously, don't compare it to BF2 and just judge it for what it is in itself. You will realize that BF2 was very good, but BF2142 is actually better, so it just makes no sense to give it a lower score.
The second problem, shared by every online game on various degrees, is the number of bugs. If you haven't jumped yet in the BF2142 bandwagon for fear of a buggy gameplay, you will be happy to know that a recent patch has made the Titan mode much, much more stable and has also fixed a lot of problems. Seriously, I haven't found any of the infamous Titan lag since patch 1.20 in any server.
The last problem would be the lack of a proper single player mode. Well, I wouldn't dream of putting a campaign mode in, say, a chess-related videogame. If you buy BF2142, you'd better expect the Multiplayer mode that made the franchise what it is today. You will find, however, a kind of skirmish single player mode with 15 bots, which is perfect for perfecting your piloting skills, testing your aim and trying the cool new toys you will eventually unlock.
There has been much talk about the ads in-game. They seem pretty innocous to me. After all, I prefer to be shown an ad for a new computer processor to, say, a random ad for some clothing company from another country.
Battlefield 2142 is, in its own right, a great and immersive online FPS that has something for every type of action player (pilots, driver, medics, snipers) and that will magically transport you for a brief time to the heat of sheer battle. Stop making excuses and play it for a good week or so. Its atmosphere is bound to suck you in.