I was in the audience, and I thought the lower-key keynote was just fine. It’s true that Jobs blew no one away. Top honchos from Twentieth Century Fox and Intel (CEO) won’t wow the crowd. Movie rentals can’t compare with the reinvention of an industry. And while Apple’s (AAPL) new ultrathin notebook looks fabulous, it’s not priced for the mass market. (And will people pay $1800 and up for a device with no Ethernet port? These are the types of topics geeks can endlessly debate.)

But so what? After a year like Apple had last year, it’d be silly to try to blow people away at Macworld. Perhaps it was better to lower expectations. I’m guessing that whether intentionally or not, that’s what Jobs did on Tuesday. And for what it’s worth, while Randy Newman isn’t as sexy as John Mayer or Kanye West, past Macworld performers, his two songs were really good.

The faithful’s disappointment had nothing on Wall Street’s, though. Apple’s shares have now fallen $19, or almost 11%, since Monday’s closing price. This will seem confusing to market watchers of the amateur variety as well as the pros. No one has answers, only guesses. Citi analyst Richard Gardner, for example, called Tuesday’s stock behavior a “typical seasonal pullback.” His explication covers all the bases:

While we are surprised by the magnitude of today’s pullback in Apple shares following an as-expected Macworld keynote, we believe the reaction reflects the view that today’s product announcements will do little to help Apple during [the first half of calendar-year 2008]. The products either represent minor enhancements to existing products (i.e., software updates for iPhone and iPod touch), niche products (i.e., the new ultraportable MacBook Air) or new services that will drive iPod and AppleTV sales over the long-term but contribute little or nothing to operating income during 2008 (i.e., iTunes movie rentals).

Trying to understand the selloff almost isn’t worth the effort. Apple is one of those stocks that defies explanation. It was equally tough to understand is recent high of almost $203.

So focus instead on how the company is valued. At $160 a share, Apple trades for about 31 times expected earnings for its year that ends in September. Analysts expect Apple to grow earnings this year about 31%, an astounding growth rate for a company this size. Next year they see 25% growth. In other words, at its current multiple, Apple is getting little or no premium to the market, despite the iPhone working out to be a bigger than expected seller and the Macintosh picking up speed. (Google (GOOG), by the way, at $616, is off 18% from its high. It trades for about 30 times expected 2008 earnings and is expected to grow by 33% … I’m just saying … )

Apple reports earnings next week. It has a habit of underpromising and overdelivering. It isn’t the expensive stock it used to be.