This Wednesday Hewlett-Packard is expected to spill the beans on its new line of WebOS tablets. But thanks to leaked photos and specs and a teaser video from the company, we already know a lot about the upcoming devices, reportedly code-named Topaz and Opal.

For starters, we know they’re glossy, black and equipped with a button-free user interface. We also know that they’re expected to have the same screen resolution as the iPad and come with front-facing cameras and access to cloud-based storage. But here’s something we don’t know: How will consumers (and developers) react to HP’s (HPQ) attempt to outcool the iPad?

HP’s signature printers and laptops fail to generate the same cult-like following that Apple’s (AAPL) products do, but the company does have fairly strong brand recognition among consumers. A recent survey from market research firm Forrester Research showed that 37% of consumers who are interested in buying a tablet said they would consider buying an HP product.

“HP has tremendous opportunity to leverage its brand strength with consumers,” says Forrester Research analyst Sarah Rotman Epps. “But we’ll see how well they tell their new story.”

Their new story is the revival of WebOS, a mobile platform developed by Palm. Last April HP acquired the struggling company for $1.2 billion. Back then, HP had said Palm’s WebOS platform would enhance its “ability to participate more aggressively in the fast-growing, highly profitable smartphone and connected mobile device markets.” The new tablets are the first fruits of HP’s WebOS integration.

But just how far can WebOS take HP on its quest to become a “cool” consumer brand, a la Apple?

UBS’s Maynard Um says tablets could open up another revenue stream for HP, but he also notes that “we are still not too bullish on the competitiveness of WebOS and believe HP demonstrating its ability to have a compelling and competitive offering based on its proprietary OS will be key to its tablet success.”

Getting consumers pumped up about WebOS could be tough—before last year’s acquisition many had written off Palm as a dying brand. That’s why HP is probably better off putting its own branding, not Palm’s, on its new tablets. But there will be other challenges, like convincing developers—who have already flocked to the iPad and Google’s Android-running devices—to create applications for WebOS.

Still, HP does have a chance to make a small dent in the iPad-dominated tablet market. It may be lousy at keeping secrets, but it’s still a powerful brand and a company with enormous marketing resources.

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