Never again would birds' song be the same.
And to do that to birds was why she came.
-- Was Robert Frost talking about the iPad in "Never Again Would Birds' Song Be the Same," 1942?

Today is a very big day for the Apple (Nasdaq: AAPL) iPad.

The most full-featured version of the tablet ships today, with 3G wireless connectivity aboard. And two of the gadget's most hotly anticipated competitors have decided to throw in the towel.

Microsoft (Nasdaq: MSFT) seemed to have a winner in the widely leaked Courier tablet, with a dual-screen design that loudly echoed a certain popular handheld gaming system. But Microsoft itself never took this concept too seriously, and now Mr. Softy is officially chopping the Courier vehicle up for parts, according to various sources. Some or all of the technology may show up in other products down the line, but Microsoft will not release Courier itself.

Meanwhile, sources at Hewlett-Packard (NYSE: HPQ) told the technology news hounds of TechCrunch that its own Slate computer is done for, unceremoniously whacked and left in a black plastic bag by the side of Highway 41.

The Slate was hyped as an iPad killer, and supposedly in development for years. This cancellation is a big surprise, because the HP Slate was a solid product, shown off to good effect at the CES consumer electronics show earlier this year. According to TechCrunch's sources, HP was simply not happy with Windows 7 as a tablet operating system, and the relatively power-hungry nature of the Intel (Nasdaq: INTC) Atom chip inside.

If this product ever rises from the dead, I suppose we should expect a different hardware platform like the less power-hungry QUALCOMM (Nasdaq: QCOM) SnapDragon chipset, paired with either the Palm (Nasdaq: PALM) WebOS software that currently runs on Palm's Pre and Pixi phones, or the Google (Nasdaq: GOOG) Android platform. Nobody knows how WebOS would perform on a larger screen, but the timing of HP axing the Slate next to its acquisition of Palm speaks volumes about HP's intentions here.

So the iPad is launching a fresh version into a relative vacuum. This model should appeal to the tech-savvy or truly mobile crowd, and the environment seems ripe for an epidemic of sellouts. This weekend will show us the stuff that the iPad is truly made of.

Blow my mind today, or forever hold your peace, Steve.

Fool contributor Anders Bylund owns shares in Google, but he holds no other position in any of the companies discussed here. And so National Poetry Month draws to a close. See you again in 2011, old friend! Intel and Microsoft are Motley Fool Inside Value picks. Google is a Motley Fool Rule Breakers recommendation. Apple and Nintendo are Motley Fool Stock Advisor selections. The Fool has created a covered strangle position on Intel. Motley Fool Options has recommended a diagonal call position on Microsoft. Try any of our Foolish newsletters today, free for 30 days. You can check out Anders' holdings and a concise bio if you like, and The Motley Fool is investors writing for investors.