Ok, well, I ordered one on Tuesday and picked it up yesterday afternoon. See what Contender has to say above. He is correct with his impressions on this gun. It handles very well and is balanced. The cuts in the barrel shroud reduce weight and help with the handling and balance. They should also reduce heat when shooting too.
The grips are large and comfortable. They don't have finger grooves, but are contoured. Since I have large hands, the grips do fit nicely. All in all, it is a "race gun" meant for competition. I can see where Ruger came up with this design. It reminds me a whole lot of the Custom Shop 1911, Look at the slide cuts in the 1911 Doug Koenig gun and it's slide sort of mirrors this GP100.
The double action trigger pull is smooth. I don't know how heavy it is, but it's definitely a smooth trigger arc, with a consistent pull the whole length. Again, with large hands, it's comfortable, smaller hands might have to stretch some. I'll have my wife handle it and see. (edited: Just did, it is too large for her to be comfortable.)
And the packaging! Ruger hit a home run with this model. It comes with an SKB hard case and a certificate of authenticity and a Ruger Coin. It's nice and shows they put some thought into how the gun will sell and probably who will buy it.
It's definitely a sharp looking gun. The grips fit perfectly. The whole appearance of this gun is well put together. It's a large gun, but the proportions are just right. Nothing seems out of place. You don't notice the shortened cylinder. And the barrel is set back does indeed mean it's a 6 inch barrel, with a smaller overall length than another gun with a 6inch barrel.
The one thing I wish they'd have done differently is have a different rear sight. I would have loved one in a dovetail cut so I could slide it out and buy a mount for one of those small red dots. That system seems to be very popular on semi autos these days. I wish it would have carried over to this gun as well. BUT! The fiber optic front sight is highly visible and gives the appearance of a red dot on the target.