Woo-hoo! No more plastic mainspring housings, either?
Colt still uses nylon mainspring housings on most of their models. Personally I don't have a problem with them. It's the plastic triggers that looked so cheap.
Another good thing about new Colts is that they use very few of the controversial MIM parts. According to a source at Colt the mag catch, sear, and disconnector are the only three parts still being made in MIM. The latest batch use machined extractors. If you have a pistol that was made a few months or more ago it might have an MIM extractor, which I recommend replacing with a quality aftermarket unit.
You can read up on the new Series 70 and 80 guns on my website.
http://usgi1911.tripod.com/series70
http://usgi1911.tripod.com/series80