Should i switch from Nikon to Canon?

I already have the Nikon D40 and i looking to buy a new DSLR. And all the pictures i seem to like are taken with a Canon. The thing is that i already have Nikon lenses, so i just wanted to know if it was worth switching/buying to Canon? OH, and the DSLRs i was looking at where the Nikon D90, D7000, D5000 and the D300s and Canon 50d and Canon 60d… Which one should i get?

Switching is the most expensive thing a person can do.

First of all, I want to say that if you like someone else's pictures more then yours, just because they have a Canon camera DOES NOT MEAN that the Canon camera had anything to do with it. It is the photographer that matters. How do you set up your shot? Do you at all set up your shot? Change your ISO, Aperture, and Shutter Speed to conform to what you are shooting?

I get much better pictures with my D40 then my friend gets with her Canon T2i. Do you know why?
It is because I go manual. I get to change all my settings. She keeps it on auto or one of the presets.

In my honest opinion, switching would not do anything for you except drain you of a couple thousand dollars. But if you are still looking to upgrade, I suggest the Nikon D90 or Nikon D7000

Both are great systems. It is the person behind the camera that makes the difference. If you want to spend a lot of money go ahead and switch. You have more money than brains. Of course in my case I have neither!

A camera brand has nothing to do with the quality of photos you see. Switching brands and buying new lenses is very expensive. You need to be comfortable with the camera, the menus, the way it feels and the basics of photography to get better photos. If you don't like the Nikon menus or the way it feels in your hands, that's a good reason to switch. If you just want better photos, spend more time practicing and researching, as switching brands won't change a thing.

If I was buying a camera today, I'd go for the D7000. The D300s is awesome, but probably a little overwhelming coming from a D40.

Switching brands is pretty expensive especially if your heavily invested in a brand. If you can afford it, go ahead it's your money.

"And all the pictures i seem to like are taken with a Canon."
Shoot raw then PP them to your taste.