HP TouchPad, the first WebOS-based HP tablet that was released on July 1, is set to welcome next month a bigger, more powerful sibling that threatens to blow Apple's iPad away.

According to leaked HP product roadmap slides published Monday by Pre Central, HP will release a white glossy 64GB TouchPad model that will sport a 1.5GHz dual-core Qualcomm Snapdragon.

The current TouchPad comes in 16/32GB and is powered by a 1.2GHz, dual-core Qualcomm Snapdragon processor.

The 64GB model is expected to have the same 9.7-inch (1024x768 pixel resolution) LED capacitive backlit multi-touch display as the current model.

It is not clear whether the new HP TouchPad will sport a better camera. The current TouchPad has a 1.3-megapixel front-facing camera for video chat but is devoid of a rear-facing camera.

The 16GB model retails for $499.99 and the 32GB for $599.99. The 64GB model is expected to retail for either $699.99 or $799.99.

The leaked slides also suggest that HP is planning an August release of a 32GB TouchPad with support for AT&T's 4G HSPA+ network.

A Pre3 smartphone and Opal, the codename for a 7-inch version of the TouchPad, is also expected to be unveiled in the third quarter. Pre Central predicts that the 7-inch tablet will be called TouchPad7.

If HP TouchPad's bigger, stronger sibling shows its face to the world next month, it will certainly pose a major threat to Apple iPad's dominance in the tablet market.

Currently, Apple's iPad remains the unchallenged king of the tablet jungle, controlling about 90 percent of the tablet market share.

In 16 months since the iPad's debut, up to 25 million units have been sold and more than 100,000 iPad-specific apps have been developed.

By comparison, there are only 300 tablet-optimized apps in Palm's App Catalog and only about 8,000 apps for WebOS, of which about 700 don't work on the TouchPad.

Moreover, unlike the iPad, which has a front- and rear-facing camera, the TouchPad only has a front-facing camera for video chat.

The TouchPad's battery also lasts only 80 percent of iPad 2's battery.

Furthermore, HP TouchPad may experience some glitches. For instance, the e-mail app sometimes may refuse to display the contents of messages. If you want to resolve it, you have to reboot the device. Also, when you rotate the screen, it takes the screen two seconds to match (an eternity for tablet users). Apps can also sometimes take forever to launch.

And, let's face it -- the TouchPad does feel like a brick when compared to the svelte, slim and light-weight iPad.

However, don't write off HP TouchPad just yet. Here's 12 reasons why: