I doubt it. WC3 modding is indeed the reason why this site was made, and it should stay a part of this site as long as wc3 modding is still performed. However, it's getting significantly less popular, and the arrival of SC2 (along with a better editor then the WC3 editor) pulled down that popularity rate even further. It's simply unavoidable that SC2 modding will have dozens of times more practitioners then WC3 modding, very soon. So in my opinion, we should definitely have at least a part of this site dedicated to SC2 modding.
Now correct me if I'm wrong, but I don't think WC3 modders will be disadvantaged in any way if we ADD a SC2 modding section. It's not going to replace it (unless the poll is bugged).
And last, but not least. There are very little differences between WC3 and SC2 modding. SC2 just allows more triggers/scripts and detailed models, but in the end you can still create a Villager model, a new skin for the Marine, a spell that causes mayhem and SFX blasts all over the place, an icon for that same spell, and everything else.
Why are you people so desperately trying to prove which type of modding is the best or which 1 was here first? Does it even matter? Both games are Blizzard products and can be modded similarly, and this site was (probably) created to help people understand the way things are modded. Do I need to say more?