Matchbox Rocky the Robot Truck!!
http://www.toysrus.com/product/index.jsp?productId=3558991#
We saw this in Toys R Us Monday and my 2 year old loved it! He's also getting the Step2 50's diner because he loves to pretend he's cooking, but DH will have a fit if I get him a kitchen set!!
http://www.toysrus.com/product/index.jsp?productId=3153188 Plus, he's very into Hot Rods/old cars and I'm going to get him some hot rod signs for his room - the diner will fit right in.
Those will be his big items. There are also a lot of Toy Story toys out there right now.
Does your son have a Tonka truck? Every little boy needs one! We have at least for - 1 regular, 1 with flames and dual wheels, and 2 mighty tonka trucks. They have always been (and still are) favorites for my boys (2 & 6).
Have you looked into Geo Trax? They are great too and now they have sets with the CARS characters.
Oh, my son got the Radio Flyer Sport Coupe (
http://www.walmart.com/catalog/product.do?product_id=10985768) for his second birthday and it a big hit with all the kids. He loves to ride in it or lower the handle and push it around himself. I can't keep him out of that.
The Step 2 Extreme Roller coaster is really cool too and gets a lot of use at my house. He may be a little small for it, but my youngest has been riding it since he was 22 months old and loves it. The car sits very low to the ground and is almost impossible to tip over.
I think we have just about every boy toy imaginable, but these are definitely his favorites! HTH!