Why does the Apple (AAPL) iPod enjoy a 71% share of the MP3 player market while Microsoft’s (MSFT) Zune limp along with a paltry 4%?

The fellows from Cupertino unload about a quarter of a million iPods a day on a music-hungry public.

Conversely, Microsoft’s latest 10-Q said that “Zune platform revenue decreased $100 million or 54%, reflecting a decrease in device sales.”

(Incidentally, many thanks to Ballmer & Company for helpfully pointing out that decreased revenue from the Zune reflects a drop in Zune sales. Really - we appreciate it.)

The numbers speak volumes: To date, there have been 3.2 million Zunes sold, compared with 170 million iPods.

Is it simply that iPods are sexier than Zunes?

Their respective customers seem to be. Take a look at one loyal Zune user who went so far as to get the Zune logo tattooed on his bicep:

Now, feast your eyes on an iPod fan:

But now, according to published reports, the fellow with the Zune tattoo, Steven Smith of Sioux City, Iowa, has become disenchanted with the wildly unpopular Zune. In fact, Smith went so far as to post this comment to the official Zune blog:

“I am done. I have had the Zune since day 1 and have noticed little improvement. I have tried my best to support them every step of the way, but... to not include Zune Marketplace or the ability to load videos from Xbox Live to your Zune made me finally give up. I am... figuring [out] the best way to get a new tattoo to cover the logo on my arm.”

The recent Xbox Live announcement at October’s E3 Expo -- an annual video game industry trade show -- made him “lose it.”

“The thing that pisses me off is that Microsoft is not advancing the Zune software. It’s obviously the bastard child in Microsoft’s product line,” Smith said in an interview with iPhoneSavior, a popular Apple blog.

Valleywag, a widely read tech site, describes the Zune as “an also-ran, late-to-market entry which mimicked the iPod but offered no new features consumers found compelling.”

They also say “The Microsoft brand is far too stodgy to succeed in an image-driven business like music,” and that the company’s refusal to finally deep-six the Zune makes the company not unlike “a wannabe politician who just can’t grasp the idea that no one wants to vote for him.”

This, friends, is why Steve Smith finally got himself a 16GB iPod Touch.

“It's super-thin and does some really neat stuff like tilting to go into cover flow,” he said. “I also like watching movies on it. I can go anywhere to get iPod accessories; that’s not the case with Zune stuff in Iowa.”

Alas, it seems as if the bloom is now off the iPod’s rose for Steven Smith. Here’s a recent post from his blog:

“Once I was a huge fan of the Microsoft Zune, but, after staggeringly bad customer service, and the player went nowhere with its WiFi idea. I gave up, went to iPod for a little while, but soon disliked that option too. That’s when I sniffed out the G2 by Slacker, and it’s exactly what I was looking for.”

Good on ya, Steve! You’re a man who takes no guff. Not from Apple, not from Microsoft…and --  let’s face it -- if you get sick of Slacker’s media player, you can always switch to a SanDisk. Or go back to cassettes.

However, with your history of rapidly-changing loyalties, do consider your next tattoo carefully.