Despite being released in both America and Japan by ATLUS earlier on in the year, due to a region lock on both the Playstation 3 and XBox360 version (A unique occurrence for the Playstation 3) those outside of these regions have been unable to import or play the game without owning either an American or Japanese console.
Zen United is set to release the game in PAL regions, aiming to narrow the gap between US and PAL release – however the company has recently announced another major delay. Specifically stating:
A 2012 release for Persona 4 Arena is now no longer possible.
So we can expect to see it on store shelves sometime in 2013 (Hopefully!). They have issued no further information, asking users to refer to their previously released FAQ (Posted on ToS HERE)