Ever since Google announced its much-rumored Google TV service last May, geeky television fans have been hankering to get a closer look at what’s promised to be the most seamless mashup of TV and the Web yet. Today at press events in San Francisco and New York, Logitech, best known for making computer mice, debuted what’s likely to be the first commercially available Google TV device.

If the 90-minute introduction in San Francisco is any indication, the Revue, as Logitech’s Google TV device is called, could deliver on the promise of a slick interface that integrates the Web with content on your TV and your digital video recorder. Despite fears that an overloaded wireless network might wreak havoc on the demo, the device quickly brought up Google searches on a large HDTV screen with a single push of a button on a keyboard-sized controller, found television content that with another button push appeared instantly on the screen, and found video stored on a DVR (though this works only with Dish Network for now).

What went unrevealed for most of the demo, however, was the price–and when Logitech confirmed that it would cost $299.99, as rumored, you could almost hear the sighs around the room of tech-savvy journalists. Unlike Apple’s Apple TV device, introduced with a much lower $99 price tag last month, and settop boxes from Roku, which start at $60, this is no impulse purchase. Apple TV and Roku boxes are very different, with a much more limited integration of Web and TV, but most consumers probably will compare them directly in their minds. Dish TV customers, new and existing, will pay only $179 for the Revue, a little better, but with a $4-a-month subscription that has a whiff of nickel-and-diming.

Logitech CEO Gerald Quindlen disagreed, saying (quite rightly) that this level of seamless integration of Web and TV isn’t available anywhere else. “I think consumers will see tremendous value in this,” he said. Still, in a holiday season when so many people will be cash-strapped, this could be a hard sell. What’s more, Sony will come out with its Google TV–an actual TV and a Blu-ray player–on Oct. 12, and it may be a little easier to hide the cost of Google TV hardware inside other products.

That’s not the only challenge. Consumers already have settop box overload, between the cable or satellite company’s box, a DVD player and/or VCR, maybe a Tivo, perhaps a Blu-ray player if you love movies, a Roku box if you love baseball–the list goes on and on. It’s a mess.

Now, Google TV does aim to provide a cleaner wrapper. But it’s still a separate box and even Google TV product manager Rishi Chandra conceded the point to me after the event. “There’s definitely a lot of device proliferation,” he says. But what Google TV is trying to do is to take the capabilities of the only device that can do most of what all those settop boxes can do–the personal computer–and bring it to the TV screen in a clean way. “It’s going to take some time” to catch on, he admits. “No one’s going to throw out all their other devices.”

All that said, Ashish Arora, Logitech’s VP and GM of its Digital Home Group, made a compelling case for the long-term success of Google TV. Every new user interface like the one Google TV is pushing requires new kinds of physical controllers, and Logitech’s at least looks like a pretty clean implementation. That’s no doubt in part because it uses Logitech’s Harmony software used in its TV remotes. That means that the Google TV hardware and software can control other devices, so you don’t have to use your DVR remote, for instance, to schedule a recording.

The keyboard controller, which is included with the Revue, looks a little large for couch potatoes, but otherwise has a slick appearance. There’s also a mini-controller about the size of a game controller but with a full thumb keyboard–though I found that keyboard a little large for comfortable thumbing. And you can also use apps on iPhones and Android phones to control Google TV, and even send video and other content you’re viewing on your phone to the TV screen.

This being Google, search is front and center. Press a button to bring up a search, and the TV or other content you were watching fades behind the search results. Click on a result, which can be a YouTube video on the Web, a recording on your DVR, or a live TV show, and you’re taken directly to it.

Although Logitech offered a few sample applications, such as Netflix, Amazon.com’s Video On Demand, and the Pandora music service, execs said a lot of the value from the Revue would come early next year. That’s when Google will open its Android Market, which will make it easy for software developers to create new apps that run on Google TV.

Finally, Logitech introduced a $149.99 Web cam for videoconferencing on your TV. It also looked pretty good, and there’s an undeniable appeal to talking to your friends and family from the comfort of your couch.

But at what price for all this? In the end, consumers will vote with the wallets, and those wallets are pretty thin these days. That’s why, even though Google TV suggests a lot of interesting possibilities for transforming the television experience–maybe even a revolution–it’s going to take awhile for that revolution to be televised.