I dunno hun, Its difficult. From my point of view, i did loads of temping between my undergrad and post grad. What you have to think about is where do u want the MA to take you? would you just got back to the same kind of job as your doing now afterwards? if so, why do an MA and hten take a step back again? On the other hand if you want to go elsewhere post MA then yeah its probably a good idea.
From my point of View, i'm just finishing my MA and am currently applying for a graduate job, but I am planning to start a PhD in a year so i suppose i'm pretending to my employers that i'll be with them in the long term when actually i will probably resign after a year and start my PhD with my current department, its naughty but atleast it gives me a good income for a year! But the only reason i'm doing that is because I want to become a lecturer so I know that I need to do the PhD. You just need to consider why you want to do the MA, I'm bored isn't really a good justification....because you could come out and be exactly whree you were before but with more debt and no job!