Here is a question I've been asked a few times: Which is better, compact interchangeable-lens or DSLR?
Compact interchangeable-lens cameras have become very popular lately. The Sony NEX-7 has been flying off the shelves and the Fuji X-Pro1 is highly anticipated. There are a number of other makes and models, as well (such as the Samsung NX200). These cameras are small and lightweight yet pack a powerful punch. With the right lens, they'll even fit in a large pocket.
Digital Single Lens Reflex cameras have been a staple for the last decade--the choice of the professional. The Nikon D800 might just be the best digital camera ever made.
Which is better? Which should you buy?
My advice is to not worry so much about this, it's not nearly as big of a deal as you think. You can craft great photographs with any camera, so use what you already have.
If you just have to get a new camera and you've got the money, you cannot go wrong with the Nikon D800. In some tests it has outperformed every other digital camera, including medium-format. You get a heck-of-a-lot of camera for $3,000 (body only). To me, this is the most obvious camera to buy. The Nikon D3200 would be my budget choice, since you get so much DSLR for so little money ($700 for the body and kit lens).
If you need something less bulky and have the money, the Fuji X-Pro1 is a great choice. With the right lenses, you can get sharpness that matches Leica. For $1,800 (body only), that's a great deal, considering how much a Leica will run you. My budget choice for a compact interchangeable-lens is the Samsung NX200, but shop around and find it on sale.
Having a small and lightweight camera is great, especially for travel and street photography. DSLRs are still king and will be as long as Nikon keeps producing amazing options for reasonable prices. Which you should buy is a personal choice, but it's not a decision to lose sleep over. Any new digital camera you buy will impress, but not one will make you a better photographer.