I'll go for both, even though I'm not rich
I've bought all the "MoM" likes so far, including Age of wonders series and elemental. There are good mods in civilization for the "fantasy" flavour, but they have gameplay constraints and graphics inheritage that make them somehow awkward, even though there are very good ideas.
I still have high hopes in Elemental because it has so many good ideas and it is dedicated to them, it's not just a mod . It feels a little bit awkward too but it'll improve. I have the feeling it might be the first of a series too Anyway I'm sure the modding tools and the team's work long after release will make last a long time and, hopefuly, time will change it's reputation.
I'll get Civ V too because "real world" flavour is fine too and because there are not so many good quality TBS and, even though it's the fifth in the serie, it's being released YEARS after the previous and I can't wait for it
Both games are not necessarily rivals, above all when they have a common ancestor (MoM was a civ like with a different flavour, just like master of orion)