I started building some modulars last month. I'm currently half way through Assembly Square (which is awesome) and my 3yr old daughter wants me to hurry up and build the ballerina studio. I have a few old road plates from the 1980s which I'll lay down in a basic layout with a train travelling around it. I have 2 Cargo trains that I have not yet built. I never had a LEGO train in my layout as a kid so I'm eager to build one. I think I'll get the new passenger train this summer and start with that.
In the interim I got one for the kids and some extra track. My daughter loves it. She gives the train a push and it whooshes! Next we have to build a train station out of her existing pieces (That her little brother will only too happily destroy... oh the joy!).