I've undergone a dramatic and fast paced weight loss - the bulk of it gone in a year. The skin issues are NOT what I envisioned, thank goodness.
I weight train, intensely and often. My arms are fine - I could and WILL proudly wear a tank top in warmer weather, they are always bared at the gym in very short sleeves. There is no evidence whatsoever that they were once much larger. My stomach is improving dramatically as I lower my body fat. The difference between my abs now and 4 months ago is remarkable - the lower my body fat, the smoother and tighter the skin. My ab muscles are visible and defined. While I haven't lost substantial weight in the past 4 months I have significantly changed my body's composition. The lower body fat makes such a great difference, it's crazy madness.
I probably sound cocky, and I don't want to sound like that. I've just worked as hard as humanly possible to fill any potential problem areas with muscle and to eat the right stuff. I know a great deal of credit can be given to genetics, but I've also put my fair share in. It's amazing, what dumbbells can do for you. People are always commenting that you could never tell I was once morbidly obese - there's not any evidence of extra skin visible (I don't wear loose clothing or try to disguise anything). A strange compliment to me, one I never envisioned I'd hear.
What suffered is my chest. Oh, my poor girls. I'm a 32 A now. But you know, that's fixable and they fed my son for 2 years. I'd never get down on myself about that. A cool thing about the weightlifting is that I'm able to create a false cleavage line on my pecs - pair that with a great bra from Victoria's and I've got a normal looking set of knockers.
FWIW, I'm 32.