I lived in the Washington DC area in Maryland many years ago. I dont know what its like right now, but I can tell you about the climate and other general things about the area in which I observed.
The winters are very mild when compared to the tri-state NY/NJ/CT areas. The temperature in MD tends to be 10-15 degrees warmer then the tri-state. You might see one or two snowfalls, but its all melted within days. Spring and Fall are great. The summers can be very hot and humid which tends to be somewhat uncomfortable at times.
There is a youthful spirit around Washington DC because there are so many colleges. I believe there is about 7 colleges in the area which are very close together and at any given time many people in their teens and twenties are out and about. The night-life and bar scene isnt as good as NYC, but its much better then many other places I have been.
The cost of living is better when compared to the tri-state area. Obviously, things like food and gas will be at a better price then what you get up north.
The people *seem*, in general, friendlier. The reason why I say "seem" is because I have learned in life that people may seem friendly at first, but talk a different story once you leave the room. Lets just say, in NYC, people are very forward and direct. In MD/DC, they are much friendlier and less direct. It depends upon which type of attitude you prefer, but in MD/DC you will get a much softer touch then in NYC.
For a single guy, its a great place. Since there are so many colleges, there seems to be a sizable dating pool and its far easier to find women then in NYC. The attitudes seem looser among the women and dating doesnt seem like a huge issue. A Bachelor playing the scene would do well for himself there and far better then in NYC.
The greatest problem with dating in NYC I have found is the attitudes. In MD/DC, those same attitudes dont seem to exist.
For a family guy, its also just as great. I wouldnt mind raising a family in that area.
I dont think you would be disappointed by moving to the DC area. Its one of the few places that I would live in if given the choice. (Those areas that I would only live in are DC, NYC, SF and Seattle.)
One other thing to note is the progressive attitude that has always existed in the DC area. There are places I have experienced where people seem very conservative and seem stuck up. I didnt encounter that in the DC area.
If you get a good offer, depending upon your situation now, I would say to go there. Its not a bad choice and I am confident you will have fun.