The problem with the arguments that most people wage in the holy war of Vinyl vs CD is that they fail to take into consideration every step in the recording and playing process. A typical vinyl zealot will formulate an argument by playing two versions of an album - one on CD and one on LP. What said audiophile has left out of his argument is the mastering and engineering of the album. Of course a rock album conceived at the pinnacle of analog recording technology will dwarf a recording made at the same time - the fetal stage of digital technology. However, not only has the recording technique and technology improved with the twenty or so years of digital sound, but the fact remains that more and more steps in the process are being done digitally. Why? I'm not a recording engineer, but I would gather that it's a combination of durability, ease of use, and cost.
The whole preference depends highly upon what kind of music you listen to. If i were into classic rock I would listen to vinyl almost exclusively. Not only did these bands record in an all analog environment during their heyday, but used record albums can be found at flea markets and record stores dirt cheap. However, if I listened to Top 10 type music on the radio, I'd buy CDs of my favorite artists (or corporate trash). Not only are these albums are produced in a digital heavy environment, if the vinyl isn't non-existent, it usually costs more than the CD, due to the lower demand.
As I listen to mainly electronic music, I am blessed by the best of both worlds. I typically buy albums on CD, as I'm sure the sound quality of something created with samplers and computers will sound better in the digital realm, and I find it somewhat of a pain to flip sides and search for tracks on vinyl. However, there are certain elusive singles that are only available as 12", thanks to this DJ heavy genre. And, call me a Luddite ape, but there is a certain satisfaction in dropping the needle and hearing the pop of it going into the groove.