All I can say is plan for the future. If you are going to keep using a DX and never plan on upgrading to a FX, you can not lose, period. When you do plan on upgrading every thing you have lens wise will work on any Nikon D series.
Name says it all; I have owned Nikon camera's from the late 70's to now; I purchased this camera to see if I still had the passion for photography I use to have, I do; I selected the D5100 because it was cheap and had great reviews.
The *only* con that I would report would be somewhat limited total control; But I know this going in, so it's not really a con