The benefit of a DSLR is ultimately, a better image. Yes, you may have to swap lenses all the time and risk getting dust all over the insides, but the range of DSLR lenses are way above what a prosumer camera could offer, though, at a price.
You can settle on a good zoom lens and never have to bother changing it again if thats what you want, or you can get one for every occasion.
If you are happy with what a good prosumer type can offer, then I would stay there, but if you always wondered if your shots could be sharper, more natural looking and with more choice of settings, then you may want to consider a DSLR.
They have a lot of downsides too. They are generally bigger and heavier and you need a big bag to carry everything about, so you risk looking a bit geeky. Everything you want to stick on the body is expensive ( you can spend thousands on a lens and £500 or more on a flash etc). But, once you have bought these, as long as you stay with that brand, you can upgrade bodies relatively cheaply.
They also generally use better components in a DSLR, hence the higher prices, but the biggest advantage is having a choice of lens that will produce exactly the results you want to acheive.
Of course, many high end non DSLR cameras are brilliant at what they do and produce fantastic pictures, but by their very nature, can be a bit of a compromise when it comes to the choice of options you require.
Of course, I could be completely wrong.....
allan