I'm planning to buy parts to make this rig:
https://en.bitcoin.it/wiki/Mining_rig#One_ATI_5830,_Approximately_245_Mhash/sIn about a month.
In a month will I still be able to get the same overall profit as I could with that now?
I realize the difficulty is increasing which means you make less bitcoins, and therefore less money, but doesn't that also mean a relative increase in the value of each bitcoin which should even it out?
There is going to a significant increase to the complexity later this week. Within a month there is likely to be additional increases. Hopefully the prices go up with the complexity but that is no certainty. You need to identify your risks and decide for yourself if it is worth it or not.