When LG announced it was throwing an Nvidia ( NVDA) Tegra 2 chip capable of 3-D display into its G2X, it sounded like we'd be getting our first look at a glasses-free 3-D smartphone. Nope. Instead, we're going to have to wait on T-Mobile to give us the LG Optimus 3-D and Sprint to debut the HTC EVO 3-D phones that, by the sound of early reviews from the CTIA wireless trade show in March, leave much to be desired when compared with the 3DS' display. In the meantime, however, LG and T-Mobile gave the U.S. its first 3-D tablet when they introduced the G-Slate on April 20. The 9-inch display, front-facing camera for video calls, more than eight hours of battery power, Wi-Fi, "4G" capability and Google ( GOOG) Android 3.0 Honeycomb OS are all secondary to the twin cameras mounted on the tablet's back for shooting 3-D photos and videos. Those videos can be displayed immediately on the G-Slate's HD screen -- with one very significant catch. At three times the size of the 3DS, the G-Slate still requires glasses for 3-D viewing. A pair comes with the tablet, but if 53% of consumers surveyed by the NPD Group in February said that the inconvenience of wearing glasses in their own homes was preventing them from buying into HD content, they're probably not going to be much more comfortable slapping on polarized shades while taking their tablet out in public. Another issue is the price, which at $520 with a two-year commitment is more expensive and onerous than buying a strictly Wi-Fi Apple ( AAPL) iPad 2. It's $70 less than the similarly performing Motorola ( MMI) Xoom, however, and $200 less than a 3G iPad with similar 32-gigabyte storage space. The not-so-minor caveat is that you need both a T-Mobile voice and data plan to get that $530 price, as the lack of a voice plan nulls a $100 rebate and an unlocked version without a T-Mobile data plan goes for a gaudy $750. Otherwise, the G-Slate is a great buy for the storage, the speed and your position ahead of the 3-D curve.