Do You Think “What You See” Influences “What You Get”?

If not, you might be wrong, as Evan at Storefront Backtalk points out in an excellent blog post.

We know the statistics: Wal-Mart's in-store TV network is now the 5th largest broadcast network in the US, after NBC, ABC, CBS and Fox. We know that YouTube and social video sites are at the top of the pack in terms of traffic, loyalty and "stickyness."  And we know that "kids these days", say anyone under 35, are tuning in to video sources on their cellphones and PDAs while on the bus or train, in class, and at work. While all of this distraction might have kept people busy, and thus not spending money, interestingly, “among the benefits of videos touted by web retailers are a lower
number of abandoned shopping carts, reduced return rates and higher
sales,” said Jeffrey Grau, eMarketer senior analyst.  Further:

[I]t’s clear retailers are just beginning to understand
the sales power of in-store videos, which is nice, because consumers
are just starting to understand the informational power—and, yes, the
convenience—that well-done videos can offer. Will these two trains
meet? And I do not mean in a Gomez Addams model train set kind of way.

The economy may also play a role. I’m hesitant to say that, because columnists, marketers and politicians (how’s that
for a trustworthy group?) today seem to find in the weak economy the
magic answers that will explain everything. (”Traditionally, Brussels
sprouts are not big sellers in school lunch programs, but with the way
the economy is headed, that’s going to change.”)

The question I have is whether there's a causal relationship between video viewing habits and purchase intent (or brand perception, or any other goal/measurement of success).  Are video watchers naturally inclined to be more accepting, hence their attitude toward watching the video in the first place?  Or are we simply seeing the self-selecting dynamic play out (as Evan notes himself)?  Or maybe it's novelty.  I guess I'm wondering how much selling the video itself is doing, and how much is coincidence.

Any thoughts?