I know this is an ancient thread by now, but I just wanted to say that I bought Mecha vs Kaiju last month and I'm getting ready to run the setting for the first time later this week.
I love this book, especially since it has mecha construction and kaiju construction rules equally in one book--without making it too big or too pricey! It could fast become my favorite "anime-style" RPG book since BESM 2nd Edition, and the fact that it's for True20 will make it a lot more appealing to my gamer friends who come from years of playing DnD, d20 Modern, Mutants and Masterminds, or other versions of d20. True 20 is simply very intuitive, and sums up the best about d20.
Mecha vs Kaiju is the one book that brought me to True20 in the first place. I got the setting book a little while before I got the core rulebook--True20 Pocket Player's Guide, in my case.
Unfortunately the Big Finger Games website seems to be gone, and the domain mechavskaiju.com is available again. I was just wondering where I could find more adventures, mecha and character write-ups for MvK, and a full list of errata.