For instance, I'm currently pretty high level enchanting/engineering on my pally (mostly ret), which was pretty imba in BC for the goggles and ring enchants, as well as a great source of cash.
In WotLK, both are still very strong professions, but not at the top of the min/max ladder. However, dropping a 445 and 380 skill for ones that may or may not be at the top of the peak in the next major content patch just doesn't strike me as very wise (ESPECIALLY for blacksmithing).
I say that if any of your current profs are above 350 at the moment, just sit tight and see what comes down the pike, then make a decision from there.
Oh, and roflcopters
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ROFLcopter...I win



