I went with the 1440p. I've got a 4800x900 setup (3x 1600x900 screens) and while it is immersive, there are a number of caveats that make it annoying.
1) FOV: I still don't understand if my screens are supposed to be flat, or if the side monitors are supposed to be angled in somewhat. Some games seem to be setup for a flat image while others seem to significantly "blow up"/enlarge the images as they near the outside edges of the side monitors. Some games are just bewildering in how they handle Nvidia Surround.
2) Support: While there are plenty of new titles that support it, a significant portion of older titles don't. So you wind up with 2 unused screens. Some games like SC2 have limits to what aspect ratios you can use. Anything wider than 16:10 is disallowed. While programs like "Flawless Widescreen" do offer support for SC2, the method of adjusting the resolution as it is stored in RAM or "memory hack" isn't really guaranteed safe. In a game like SC2 where competition is taken very seriously and there are anti-cheat measures in place, I'd be worried about using something that's modifying memory as a long-term solution.
3) Heat: My array really brings the pain to my 2 GTX 480's, and I'm not sure the experience is really worth the heat generation. Where 2560x1440 yields 3.68 megapixels, 5760x1200 is 6.912 and that's without any sort of bezel correction, which realistically you'd want to use. That's a significant difference in the amount of work the GPU is going to have to do, and the triple screen resolution will just devour VRAM.
4) Monitor Orientation: Even just getting the monitors to sit right and level can be a challenge. The rounded bezels on some monitors can cause the monitors to not touch evenly, sometimes forcing space to be left between them (which is rather unsightly). Unless your desk is one surface, or you get a 3 monitor mount, it's going to be difficult to get them "just right".
With all that, there is something to be said for the productivity advantage of 3 monitors. I enjoy having a wide desktop with a variety of open programs.
The thing keeping me from taking the leap to a 1440p monitor is that they're price-gougingly expensive at the moment. The Auria 27" is probably the cheapest I'd want to go, and even its expensive. The Korean companies like Shimian and Crossover offer compelling products, but the sparse support of HDCP, scaling boards, and international returns steered me clear. I'm still trying to understand how devices like tablets and smartphones are coming out with screens with dramatically higher pixel densities than those offered by 1440p monitors and for a fraction of the cost. Why a 5" 1080p screen is considerably cheaper than a 27" 1440p screen is just perplexing. Obviously, there's differences in display technologies as the 1440p is IPS and the 1080p screen on a number of small devices is AMOLED, but it still confuses me. I'm hoping that eventually 4K displays will drive QHD displays down to a reasonable price.