Why haven't Android tablets enjoyed success similar to Android smartphones or Apple's (Nasdaq: AAPL) iPad? According to NVIDIA's (Nasdaq: NVDA) CEO:

It's a point-of-sales problem. It's an expertise-at-retail problem. It's a marketing problem to consumers. It is a price-point problem. And it's a software richness of content problem.

Motorola Mobility's (NYSE: MMI) CEO adds, "Consumers want more apps for Android tablets."   

Whoa! Enough, already! Android tablet sales were supposed to take off once they featured the Honeycomb version, which was developed for tablets. But in the first quarter, Motorola Mobility shipped a total of only 250,000 Xoom tablets. By comparison, about 1 million iPad 2s sold the first weekend it was available.

NVIDIA's CEO cares because his company's Tegra 2 chip is the brains behind both the Xoom and Samsung's Galaxy Tab 10.1. He believes the problems are getting solved, with tablet manufacturers adjusting their plans and Best Buy (NYSE: BBY) setting up a dedicated location called Tablet Central.

That's nice, but I still think the advantage goes to Apple. My experiences shopping at Best Buy have sent me to Amazon.com, whereas my experiences at Apple's retail stores keep me coming back. I also suspect that Apple will remain first in line for apps, given its huge installed base.

Although one or more Android tablets are expected to be among the top tablet runners-up to the iPad, lukewarm Android tablets sales don't bode well for Motorola Mobility, Samsung,Dell (Nasdaq: DELL), Research In Motion (Nasdaq: RIMM), or Sony. (RIM's PlayBook can run Android apps in what appeared to be an unsuccessful eleventh-hour attempt to make the product more compelling.) Sony at least has a unique and attractive product design working in its favor.

Hewlett-Packard's (NYSE: HPQ) forthcoming webOS-based TouchPad could face many of the same hurdles as Android tablets. Getting app developers' attention could be even tougher than for Android. HP does have a strong retail presence, but it falls well short of Apple's retail savvy. HP's consumer marketing is vastly improved in recent years, too, but again it falls short of Apple's. On a brighter note, there are indications that when it comes to the core operating system, HP's webOS is in the same league as Apple's iOS and ahead of Android.

Foolish takeaway
The tablet runners-up may wind up looking like the horses that followed Secretariat across the finish line at the Kentucky Derby, and when it comes to business, coming in a distant second or third doesn't pay off as well as running a close race.

Which tablets will be runners-up to the iPad, and will they win any meaningful tablet market share? An easy way to stay on top of market developments is The Motley Fool's free new My Watchlist feature. You can get up-to-date news and analysis by adding these stocks to your Watchlist now.