SAN FRANCISCO -- Can Apple keep the revolution going with the second version of the iPad?

Amid intense competition from nearly every computer and phone maker on the planet -- and growing regulatory concerns about its dominant position and business practices -- Apple is launching the next version of its tablet computing device today.

The device is slimmer, more powerful and has a camera, but it may need more than just a performance boost to maintain Apple's roughly 90 percent share of the incendiary market for slate-like computers.

Apple may also use the launch event to announce new online "cloud" services that would bring new capabilities to the iPad and other connected devices.

Adding to the drama are ongoing concens about the health of Apple Chief Executive Steve Jobs, who took a medical leave in January.

Jobs opened the event with a big applause. "We've been working on this product for awhile and I didn't want to miss today," he said.

Apple just passed 200 million accounts with credit cards and one-click purchasing, he said, suggesing that it's outpacing Amazon.com.

Jobs said 2010 was the "year of the iPad" with 15 million units sold, taking 90 percent of the market. Jobs said that's more than all TabletPC's ever sold, and that Microsoft's slate computer didn't invent the modern concept - it "crashed and burned," he said.

Apple also recently sold its 100 millionth iPhone and royalties on applications sold through iTunes reached $2 billion.

The new iPad, Jobs said, is based on a new "A5" processor. It's a dual-core processor that's up to twice as fast and graphics are up to nine times faster than the A4 processor used in the first iPad.

Others are starting to ship dual-core tablets but the iPad 2 will be the first to ship "in volume," Jobs said.

The new iPad has a rear-camer and a front-facing camera and now includes the gyroscope used in the iPhone and iPod Touch.

It's also "dramatically thinner -- not a little bit thinner, a third thinner," he said.

The iPad 2 is 33 percent thinner -- from 13.4 millimeters to 8.8 millimeters -- and thinner than the iPhone 4. It also weighs a bit less -- 1.3 pounds, vs. the previous 1.5 -- and it comes in white as well as black.

"We're going to be shipping white from Day 1," he said.

Battery life will still be 10 hours for the iPad. The prices will be the same as the current iPad -- $499 to $829, depending memory size and wireless capabilities.

The new iPad will be available with 3G service on both AT&T and Verizon networks at launch.

"We think 2011 is going to be the year of iPad 2," Jobs said.

It's going to ship on March 11 in the U.S., quelling recent concerns that the device had slipped to June.

An additional 26 countries will get the device on March 25.

Jobs also announced a new $39 HDMI video cable and new "smart" covers to protect the iPad's glass face. The covers wake the iPad when opened automatically, and use magnets to attach and align the covers. They'll cost $39 for a polyurethane version and $69 for a leather version.

Also announced is version 4.3 of the iOS software used in the iPad. New features include a home-sharing feature and update to AirPlay for streaming media in the home.

The new software also lets iPad users choose whether to use the slider switch that locks the screen rotation to instead mute the iPad.

With the software and the new iPad's front-facing camera, the device can be used with Apple's FaceTime videoconferencing feature to chat with users of newer Apple phones and Macs.

The new software will be available free, also on March 11, to iPad, iPhone 4 and iPhone 3GS devices.

Also announced were new iMovie and GarageBand applications, each of which will sell for $4.99 starting March 11.

Jobs concluded with a soliloquy about Apple's approach and the iPad being a "post PC" device that will prevail over competitors developed from a PC perspective.

"It's in Apple's DNA that technology alone is not enough -- it's technology married with liberal arts, married with the humanities, that yields us the result that makes our heart sing and nowhere is that more true than in these post PC devices. A lot of folks in this tablet market are rushing in and they're looking at this as the next PC. The hardware and software are done by different companies and they're talking about speeds and feeds just like they did with PCs.

Our experience and every bone in our body says that is not the right approach to this. These are post-PC devices that need to be even easier to use than a PC ... where the software and the hardware and the applications need to intertwine in a more seamless way than they do on a PC. We think we're on the right track with this."