Worth it to upgrade to Nikon D90?

Yes if you need it... I shot with a D40 for a while and took some great shots. But the D40 couldn't handle some of the lenses I was looking to get into specifically the 50mm 1.4 or the 1.8 at that. No autofocus on these lenses with the D40. So I step up to the D90 as I don't need th D300 or the 700 just yet. The D90 handles so much nicer. The giant screen (compared to the D40) is fantastic not only for previewing images but for controlling all your settings. ISO's are very nice and I couldn't be happier with the purchase. I picked up a D80 recently and love it also but the 90 still takes it by a long shot! I say get a D90...

Nancy, I am also an amateur but feel if I would go professional I would upgrade to the D300 or D700. I would also have to bite the bullet and purchase some serious professional lenses, flashes, and tripod with a ball head. So my question is what do you have for lenses and what type of photography do you want to sell?

Obviously the D90 has quite a few features missing in the D40x. I would take a look at what those features and options are, see how many were important to me, then decide if it's worth the extra money. I certainly wouldn't be upgrading only for a DOF preview but of course, you would be getting much more than that.

the main advantage IMO is the internal motor in the d90, which gives you tremendous versatility in terms of lens selection. there are other differences as well, like two command dials, larger LCD, and more fps.
a d40x>d90 move would be a modest upgrade, as you won't see much difference in IQ at low ISOs. but definitely an upgrade nonetheless. if you plan on expanding your glass arsenal, it's a good idea.
but before upgrading, it's always a good idea to ask yourself, "what can't i do with my current camera"? and "would the $$ i spend on a new body be more useful if i spent it on lenses, external lighting, tripod/ballhead, etc."

The D90 had features you don't get with the D40--it will use autofocus lenses without internal motors. If you are serious I would think the D90 would be a good fit. I think you would be happier with it than with the D300 as you probably don't need a body that will handle MF lenses and the D90 is smaller and lighter than the D300.

So my question is what do you have for lenses and what type of photography do you want to sell?

I have an 18-135, a 105 Micro-Nikkor and a 70-300 zoom, the latter two with VR (and plan on replacing the 18-135 for a decent piece of glass). I have indeed found the lack of that internal motor a bit limiting indeed when it comes to purchasing lenses. As for what genre of photography I'd be aiming to eventually sell, it would be primarily what I call "intimate landscapes".

Nancy, I am also an amateur but feel if I would go professional I would upgrade to the D300 or D700.

Tim, I agree, but as I'm not quite there yet, I feel something in between entry level and pro is right for me at the moment. That is, if the D90 can be considered somewhere in the middle....

I agree with the first response. I went from a D40 to the D90 after much agonizing. I was looking at the D90 vs D300 at the time. I'm glad I went with the D90 and am saving up for the D700. The ISO capability between the 40 and 90 is light and day. I think its also improved over the D80 and 70. It's also really nice to get access to a lot of features without going into the menu like the D40. Buying better equipment just makes you want more.

I love the D90. I don't know what advantages you're hoping to achieve. Upgrading your camera will not upgrade your images at all. Use what you like to use, that's all a camera changes--the usability.

This is very helpful for me. I am a D40x owner seriously eyeing the D90 or D300...makes me want it more!