I think Gamespot ripped it from another site. I read this earlier on:http://news.com.com/2100-1043_3-6140298.html?part=rss&tag=2547-1_3-0-5&subj=news
I don't see how they can regulate it. Accounts are usually sold under the table (and in the case of WoW, at least, not condoned by the company) so the only real way to tax it would be if ebay or ige (unlikely) would add the tax themselves. It's hard to say which players will end up selling something and which won't. I think we all agree that taxing individual items is absurd and would destroy the game. Of course, this is strictly from a WoW viewpoint. I can't really speak for Second Life since I know nothing about it.
I don't know how this could affect gold sellers since most of them are based in China. The only way I can see them being taxed is through ebay. Seems like Blizzard has cracked down on ebay sales though.
This reminds me of all the "you are buying my time" disclaimers on wow auctions. like that would ever hold up if this came into action.
To sum it up: I'm not really worried about it. It looks to be one person's opinion and there isn't any legislation going through anywhere yet. Also, I know these things can take awhile to ever come into effect anyway.