Although some of the new projects (The Emerald, Pure, Zen, The RD650) are getting press for the fact that the construction of these new higher-rise buildings will bring an ultra-modern, sleeker look to the West Loop, I'm personally still a fan of the smaller, low to mid-rise loft buildings that give the West Loop the artsy, industrial feel.
Some examples: Sky-tech Lofts at 6 S. Laflin, Olympia Lofts at 843 W. Adams, 850 W. Adams (upscale lofts - huge!) 1000 W. Adams (I like it even though it is a bigger more modern building, and assessments tend to be high. Supposedly, though, the heating bills are minimal in this building due to high-efficiency heating /cooling systems); 7 S. Aberdeen (another upscale loft building)... many more.
If you want to a pretty complete list of condo buildings in the West Loop, go here: http://www.westloop.org/live/
The West Loop is definitely booming with its trendy restaurants and industrial/artsy/professional vibe, but maybe too much so. The area is pretty saturated with condos right now, and sellers are looking at averages of 4-6 month market times. It's a great area, though!