At least ratings-wise, the head-to-head competition between these two shows is over before it really starts. Lost routinely clobbers any and all competition. However, both Lost and Veronica Mars head the primetime charge towards the continuing, serialized narrative, though each program approaches serialism with a significantly different philosophy.
Although both shows center around a dominant mystery, Lost, on an episode-by-episode basis, typically offers a mystery that has a direct consequence on the show's mythology (i.e. what is the island, why are survivors there, etc.), but more often than not in season 2, the episode fails to resolve the mystery so that a later episode to grapple with. An episode of Veronica Mars on the other hand introduces a small plot that may or may not be related to the larger mythology (in season one, who killed Lilly Kane; in season two, who sabotaged the school bus), and unlike Lost, the episode resolves that mystery before its 42 minutes are up. And just as importantly, that episode of Veronica Mars will also sneak in a new mystery right at the end. These two different serial approaches have profoundly different effects on the viewer (though I must warn that I'm once again generalizing from my individual experience).
In order to talk about Lost's approach to mystery and cliffhangers, it's best if I first talk about cliffhangers in Veronica Mars. When an episode opens with a new, minor mystery, the viewer feels incomplete in a very basic sense: she doesn't know Who Did It or What Happened, and she wants to know. So of course, when the mystery is solved, the viewer feels completed with the knowledge. But when the episode, in typical Veronica Mars fashion, introduces another mystery or a new clue in the mythological mystery, Veronica Mars displays a thorough understanding of both an ongoing television show and the capacious and bottomless appetite of human desire.
The American model of a TV program and the mechanism of human desire run parallel to each other. Television programs always want their viewers to come back for more because as money-making enterprises, they need to maintain their number of viewers from one episode to the next to remain attractive to advertising dollars; meanwhile, viewes are happy to oblige the programs because people will always desire that one object that will make them whole and complete. But of course, even if they get the object of desire, they'll soon find something else that they're missing and will want once again. So, when Veronica Mars ends an episode with a new mystery or a new wrinkle in an existing mystery, the show enacts both the American TV model and viewers' psychological inclinations.
With its method of introducing new mysteries, Veronica Mars also treats viewers with a pang of pleasure. After an episode resolves its mystery, the viewer feels satisfied and complete, but this sense of wholeness is quickly shattered by the new mystery. Yet, instead of feeling distressed by the new mystery (and the lack of knowledge that comes with it), our unconscious mechanism of desire is stimulated. People want to want, and Veronica Mars taps such an impulse by persuading the viewer to want to know Who Did It or What Happens Next.
Lost, in contrast to Veronica Mars, is much stingier with its mysteries, which resultsin fewer mystery plots. And with fewer mysteries (which usually are stretched out across multiple episodes), resolutions are likewise harder to come by. Ultimately, the entire mechanism of desire is frustrated. Although people want to want, they want to want new things, and Lost often doesn't deliver new mysteries because it's fully intent on milking the Island mystery. Take "The Whole Truth" (2x16), for example. It centers around the Henry Gale mystery (initiated two episodes ago with "One of Them" (2x14)): is Gale an Other or not? This episode begins with this question in the air (I won't usually count flashbacks as new mystery plots because they're not very interesting most of the time) and ends with it still unanswered. Consequently, the viewer is unfulfilled and incomplete, which is a regular feeling since Lost stopped offering new twists and turns and instead focused on stringing its viewers along with old mysteries.
That Veronica Mars seems to wield an innate understanding of Lacanian psychoanalysis (i.e. the mechanism of desire, for those of you keeping track) doesn't mean that its method is perfect. As season two has shown, the show's directive of one new mystery per week seems to be straining its internal logic and credibility. After all, it's only a matter of time when such a proliferation of ideas caves in on itself, leaving viewers with "One Angry Veronica" and "Ain't No Magic Mountain High Enough."
Still, it's notable that Veronica Mars dares to incorporate so many mysteries, especially since most other serial shows adhere to the Lost-style -- Alias and 24 spring to mind most readily.
Indie rating: Drive Like Jehu - "Human Interest"