Originally Posted by
skyliner
Ubuntu still recommends the 32bit version regardless of what your browser headers report.
If I'm not to late I'd recommend you to get Kubuntu 12.10 instead. You get all the benefits of the *buntu family, such as the huge software repository, the convenience and support of being the most used distro. Plus you'll get the "improvements" the new Kubuntu maintainers are implementing (they aren't related to Canonical). On top of that you get to use KDE by default, instead of Unity, which to me is the biggest advantage.
Oh and do get the 64 bit if you have more than 3GB of RAM, or plan on getting more in the future.