Anyway, in for Sg weddings it's very hard to justify a 1DsM2, and 5D price/function is still not justifiable yet, like the 1DM2 I'm still waiting for some features to be implemented. If I get 1DM3, I can also use it for birding. Most of my considerations depends on frequency of use.
Also, I need a backup and it will be 10D till it dies on me then I'll look for another 1.6x just because of cost factor. I'm considering should I get EF-S 17-55/2.8 but it's too expensive as I will hardly use it.