Yes, I have the 18-55VR also and used to have the 18-135. I just found that switching lenses and carrying them around, although it has a big cool factor, is just a pita and then you get dirt inside.. it has 0-wife to take picture factor. Its just easier with one lens and the lens is GREAT. Also, the 135 didnt have enough range for normal shooting. 200mm is just about right. The pics it takes are amazing. The only place it fails is in low light indoors. For this I bought a 50mm fixed lens and it doesnt require a flash, so its good for babies, etc. I dont really need this lens though, just the 18-200Vr. VR btw is worth the money.
One other thing about lenses with large/long barrels- you need to use an external flash because the barrel blocks the on-board flash. You need to use a flash anyway when shooting. the pictures come out so nice using TTL. I recommend getting this stuff for the perfect d40 or d40x setup:
BTW, I use the larger sb-800 ones, but unless you are taking pics with remote flashes, its not worth the extra money - I think the 600 has about the same flash power.