All four national US wireless carriers announced last week that they'll sell Samsung 's  Android-based tablet this fall, and Samsung disclosed a series of media partnerships aimed at making its Galaxy Tab a viable competitor to Apple's iPad.

Verizon Wireless, AT&T Mobility, Sprint Nextel and T-Mobile in separate announcements said they will offer the 7-inch tablet based on the latest release of Google's Android mobile OS, though none offered details on pricing or specific release dates. Verizon said it will launch the tablet in the "coming weeks," AT&T in the "coming months," Sprint by "this fall," and T-Mobile said "for the holiday season." At a press conference in New York, Samsung said it would launch a Media Hub services with partners including MTV, NBC, Paramount and Universal Home Entertainment, designed to be competitive with Apple's recently revamped Apple TV service.

Samsung said this week it has shipped more than 1 million Galaxy S smartphones in the U.S., roughly six weeks after they were put on sale along side the iPhone 4 at AT&T and to T-Mobile subscribers.

Though they aren't iPhone 4 or iPad uptake numbers, sales of Samsung's Android-based phone does give the Android camp a hot-selling model to go head-to-head against Apple, and Research in Motion, which has seen lackluster sales of its new BlackBerry Torch, the first model sporting the new BlackBerry OS 6. Android's momentum has been well documented, most recently by Gartner when it reported that smartphone makers had shipped 11.2 million Android-based devices in the second quarter, or 17.2 percent of the worldwide market, up from a mere 1.8 percent in the second quarter of 2009. Yet much of Android's success has been attributed to the fact that there are dozens of makers and models of Android phones, offered by all the major wireless carriers, while the iPhone remains exclusively on AT&T in the U.S. and RIM is the sole supplier of the Blackberry.

Sprint Nextel can't keep its EVO 4G smartphone in stock in some places, the company's chief executive, Dan Hesse, said on Tuesday, citing "better-than-expected demand," rather than the rumored component shortages. 

"The device is more popular than we or HTC could foresee," he told reporters, according to Reuters, after his keynote presentation at a Forrester Customer Experience conference. The EVO 4G, made by HTC, is Sprint's first WiMax-compatible phone and has been selling briskly since it's launch on June 4, though not as briskly as Sprint first announced. The carrier had to backtrack on it initial public  announcement that it had sold three times the number of EVOs than its two best-selling phones – the Samsung Instinct and Palm Pre – combined over their first three days of availability.

Yesterday Hesse specifically said he didn't think lack of key components was the issue, even though the screen of the EVO is made by Samsung, which is supplying it's own touch-screen Galaxy S smartphone to all four national wireless carriers, including Sprint. Is there really a difference between a parts shortage and too-strong demand for a device? Either way, would-be buyers can't get their hands on it, and have more time to consider other options, like the new iPhone 4, which Apple was able to supply in first-day volume nearing 2 million.

Sprint Nextel, majority owner in WiMAX provider Clearwire Corp., is reselling WiMAX service under the Sprint 4G name in US markets that include 30 million people. And Sprint's president of Business Markets, Paget Alves, tells Forbes that Sprint's new 4G smartphone will debut months earlier than expected, within the first half of this year.

Sprint began its 4G network rollout in 2008 and has introduced various devices for connecting to it, including USB modems, PC cards and "mobile hotspots," but smartphones that exploit the network that Sprint says is 10 times faster than its current 3G system have been conspicuously missing. The first new model will reportedly be a touch-screen phone designed by Taiwan's HTC, running Google's Android operating system, and will be dual-mode that can automatically switch between Sprint's 3G and 4G networks.