ea, if you use Blitz as the client, don't see what value HTML will bring.
It will bring the ability of people easily installing servers on their websites such as by having a simple account at Brinkster or whatever. If you allow minor rule changes to the game itself by the server admin, you make the possibility of having different flavours of games. However, you are right to conclude this being a MASSIVELY m.o.g it might not be so wise to have too many servers. Maybe the html solution would be better for smaller games with about 80 players max so that groups of people can launch a server as easily as a website. Not many people know how to configure a server properly for any game.
Id say just use PHP on the server to make and load pure text files( not HTML)
Clever. Its what i'd come up with if i had given the idea more than 78.4 seconds of consideration.
As for GCP, lucky we got Blitz now ey? I'm sure you'll prove yourself here quite well :)