My review of the DTS can be read
here.
Once upon a time Cadillacs had names that were intended to recall the romance of Spain. Which at the time many of these names were first applied to Cadillacs was ruled by Franco's fascist government. But that's beside the point.
The European luxury makes have long used alphanumeric names. At one time there were words being those used by Mercedes, but even then Americans had no idea what the names meant.
In recent decades many American makes have flirted with similar alphanumeric names. Pontiac is currently experimenting with them for at least the second time despite a failed attempt in the 1980s.
With Lexus and Infiniti adopting similar naming strategies it was perhaps a matter of time before Cadillac followed suit. And so in place of Catera, Seville, and DeVille we now have the CTS, STS, and DTS, with the "TS" perhaps still standing for "touring sedan." The Escalade is the sole Cadillac with a real name, and I wouldn't be surprised if that name is chucked as well when the SUV is redesigned next year. We'll then have an EXT, ESV, and whatever the regular wheelbase one can be called.
I personally do not care for these non-names, but then DeVille was quite musty. Maybe after a few years with these alphanumerics Cadillac can adopt some real names again, but without any baggage.
Update: Now Lincoln is jumping on this inane bandwagon. I suppose in a few years names will be back, as these companies can never maintain a particular direction for long.