Baby Jogger's been listening to its customers and has heard the call for a longer seat. The new Summit X3 ($429) has a wider and taller seat than the second generation buggy, offering more headroom for tall kids. But most exciting is the new remote swivel wheel lock, which eliminates the need for mom to lock the wheel in jogging mode by hand. The stroller, which will debut in the Spring, will also be made into a double ($649).