Is it worth upgrading from the Nikon d3000 to later models?

I have had the D3000 for about 4 years now and I find it quite limiting in it's manual mode. I'd like to learn more about proper photography rather than "point and shoot" but I feel like the D3000 is not very comprehensive when it comes to manual mode. Firstly am I just making this up?
And if I were to upgrade, what camera would you suggest? I was looking at the D5100 but I'm wondering if it's worth upgrading to that since it seems pretty similar to the D3000 (correct me if I'm wrong?)
I was also considering the D7000 but I don't have a lot of experience shooting in manual mode. Will the step up be too complicated or should I just try it?
(only really looking for Nikons.)

The best way for someone (that is genuinely interested) to learn more about photography is by reading a photography guide book… You can pop into a local library and flick through what they have and it won't cost you anything.

The manual mode on your DSLR isn't any different from the manual mode on any other DSLR… The image sensor has been updated and you might find some more additional features on newer models, that's all.

If you were really interested in photography you would already know this… That might come across as 'cheeky'… It's true though. There isn't any point in advising you to 'upgrade' your camera because nothing much is going to change… The most important thing to improve that will affect your images is your knowledge… The more you begin to understand about your camera and photography, the better your images will become.

What's wrong with manual mode?
all cameras work in the same way: set ( the right ) aperture/esposure/iso an then take a photo… You can do it with your D3000 ad well with a D4s ;-)

Yes you are making this up. Manual mode in the D3000 will be exactly the same as the D5100 and exactly the same as the D7000 and any other Nikon (or other DSLR you care to name).

If you can't use manual mode in the D3000, you won't manage it in the other models either. You get better at photography by learning, not by spending.

Manual mode is not difficult IF you understand the principles of photography, particularly exposure, ie how to balance ISO, aperture & shutter speed. Take a course or join a local camera club and get some tuition.

If you were to upgrade, no point in the D5100, I'd go for the D7000 (or D7100) as it has a focus motor in the body & will allow a greater range of AF lenses to be used.

Yes you're making it up.

A D3000 has full manual mode no different from the most expensive DSLR you could buy. Manual mode is the one in which you can set the aperture, shutter speed, and ISO. And your camera has that already. If you are having problems using it, read your user manual - especially the part about using the internal light meter in your camera, then go read this: Understanding Exposure: http://www.cambridgeincolour.com/...posure.htm

A D3000 is a DSLR, not a "point and shoot". If you can't work the camera you have, and get good shots, then I'm afraid buying a new camera will not help. You already have everything you need to learn "proper photography" - the rest is in your hands.

The D3000 was a major mistake by Nikon. It was released at a time when every other comparably priced DSLR being released had Live View and video capability - both lacking on the D3000. The D3000 also retained the CCD sensor of the earlier D40x when all other DSLRs of comparable price were switching to a CMOS sensor. Nikon quickly dropped the D3000 and introduced the D3100 which added the three features missing on the D3000.

However, having said all that, shooting in Manual Mode will be the same on any DSLR regardless of price. Check the light meter and adjust aperture and shutter speed to produce a correct exposure.

So the only reason to upgrade would be to have a CMOS sensor, video and Live View.

No need in me repeating the same answer as the others, but I will say that what you actually need is a book such as this:

http://www.amazon.com/...81740502X/

What you are saying about your camera and thinking another camera is going to change indicates a major lack of knowledge on your part. Education is what you need, not another camera. Though you likely do not consider yourself a "beginner", your skill set appears to be at that point.