Jonathan is starting to be quite determined in his attempts to reach things just beyond his grasp. He'll be sitting up, and will lean over forward as far as he can, and then kick his legs out behind him (at this point hopefully his hands are out in front ready to catch himself!) Then once on his tummy he wiggles his legs with lots of emphasis and little result as he tries to manuever his body just a few inches closer to the desired toy. It's quite cute to watch, and fun to see him get closer and closer to being mobile (yikes!) :)
Oh, and he's also rolling over again. He had stopped doing that entirely for a couple of months, and now he wants to do so again. There are just so many fascinating things just out of reach!