My question is simple does the total map count includes 3 forge worlds or not. I guess everyone would be greedy and hope that the 3 forge worlds are not part of the total map count.
I think that the total map count will not include the 3 forge worlds because the one forge world shown was not playable in its current state.
343 said 3 new worlds to forge on. That statement says it all but its bland. So the original forge world might be included. Who knows?
forge has probably been the least talked about subject considering we havent seen much of it. im sure as we get to pax prime 343 will reveal more forge.
3 forge maps + 10 multiplayer maps = 13 default maps in Halo 4. 
Add the spartan ops maps., +50
At the 10th week.
> 3 forge maps + 10 multiplayer maps = 13 default maps in Halo 4.
One can dream 
They may just release 1 forge map with the initial 10 maps and through future DLC they have more maps release? Anything is possible to be honest.
I believe that the 3 Forge maps are in addition to the other 10 multiplayer maps, making a total of 13 multiplayer maps.