New Hoods - Are we limited to only what comes with the game?

1.  Will we be able to have Hoods we can create like they have in Sims2? In Sims2 we can create our Hoods with our own lots and sims.

2.  Are we limited how many Sims we can play in one hood?  By creating Sims in the Demo, there are many,  but we are limited to how many lots/Sims are in one Hood?