I came back to re-address my comment above.
I still say buy it. I had a good time with it until I became very very bored with how shallow it feels. It's now sitting there unplayed for the last week. I WILL play it again, probably at 1.1 where Froggy said the real changes are happening, not 1.08. So, in the meantime, I'll play Civ5 when it gets here. To me, it's not a Civ5 vs EWoM issue.. I think both will be great.
But still, buy it, you may enjoy it longer than I did and maybe by then the changes that actually make it a bit deeper and more exciting will have come into effect. I think, in the end, you'll buy it, so why not get something out of the same money instead of delaying it a while longer. I'm bored now, but I will be back to play it and I'm sure I'll enjoy it... eventually.