Holy shit! We're at 30 nominations so far...my nomination of Antrhax will bring it to 31. I'm thinking that since Slayer and Megadeth have also previously been nominated, that I should include Metallica just to have the "original big four" represented in the tournament.
Therefore, we are at 32 bands as of now. If there are any more nominations at this point, we may have to expand the first round to a whopping 32 matches of 64 bands... so I'm tempted to close nominations at this point, unless someone can make a strong argument for other bands that haven't been nominated (ie. I'm surprised there hasn't been any mention of Iron Maiden...)