Here are my results from doing so A/Bing Vinyl vs. Digital.
System: An almost new Technics SL-10 with original cart with a Cambridge 640P with Pangea P100 PS vs. an Oppo BDP-83.
Speakers were KEF 104/2s; Amp and Preamp at the time was Kavent S-33 preamp and Kavent P3300 amp combo.
Specs of gear: http://www.kellsieavdesign.com/products/S33-P3300.htm
We listened to a bunch of alt rock records (Depeche Mode, The Cure, Garbage, etc) as these were the only records and CDs we had available.
A lot of us found the difference between swapping between the sources was in this set-up was the music from vinyl was just a lot more relaxed. The music from the Oppo had a bit more boominess in the bass and was a tad more forward. With vinyl the music had a bit more resolution and detail with no fatigue but the volume had to be turned up a little more.
When we were done playing records that afternoon and started discussing things it mostly came down to preference. One listener liked the oomph the Digital recordings had. Another listener enjoyed the vinyl sound. One didn't like the fact that it was such a process to clean the record before and after playing while another didn't mind the process. I think on one Depeche Mode album the CD sounded more treble heavy and there was a bit of harshness in the music.