engine - 5:09 pm on Apr 18, 2012 (gmt 0)
It seems to me like the negative match list is going to have to expand, assuming it'll work like that.
I did note this from the announcement.
If you don’t want the potential for more clicks and prefer to maintain the current matching behavior in your campaign, you’ll still have that option. In the coming weeks, we’ll begin rolling out controls which will allow you to adjust your keyword matching options.
So, perhaps there will be an option to deselect the new matching.