Not sure how much investment is going on in Carrick, not much I would guess. There never really has been, and any local industry usually closes down with a serious impact on the town (e.g. Sram recently).
As stated it is more of a commuter town and investment usually goes to the areas nearby - Waterford, Clonmel, Kilkenny etc. There should be no shortage of people to employ though, Carrick is still running one of the highest unemployment rates in ireland at around 25% when i think the national average is around 4-6% (well it was in the last report - 2004 Strategic Development Plan). Hope this helps, I wish you all the luck in the world if you are planning on investing there, remember though that you will be competing with the towns listed above because people from Carrick would usually travel and spend there rather than spend locally thus again negaitvely impacting the area.