It may seem like 2010 was the year of the tablet, but the reality is that 2010 was really just the year of the iPad with 15 million units sold and no real competitors for the Apple tablet. However, 2011 will be very different with a diverse variety of tablet options emerging--including some particularly relevant entries from major players.At CES 2011, almost every tech vendor in existence made some sort of announcement or displayed some sort of prototype of a tablet. There are big tablets, small tablets, Android tablets, Windows tablets, and everything in between slated to hit the streets at some point in the not too distant future.The tablets that stand out the most, though, are the Motorola Xoom--built to run the upcoming Android Honeycomb designed specifically with tablets in mind, the BlackBerry PlayBook--running a version of QNX rather than the BlackBerry OS, and the HP WebOS tablet--running, well--WebOS. Pit those three against the expected iPad 2, and the spring of 2011 will be a very exciting one indeed for tablets.Let's look at the choices in more detail:Motorola XoomThe Motorola Xoom is expected to be the first tablet out of the gate running Android 3.0--a.k.a. "Honeycomb". Unlike the pint-sized Samsung Galaxy Tab doomed to running Android 2.2, the Xoom will sport a 10.1-inch touchscreen. The Xoom will also have 1280-by-800 resolution, 1GB RAM, a 1GHz processor, 32GB of internal storage, an SD card slot, 3G (and maybe 4G) and 802.11n Wi-Fi connectivity, a 5 megapixel rear-facing camera with 720p video capture, and 2 megapixel front-facing camera for video chat.BlackBerry PlayBookRIM's BlackBerry PlayBook has a smaller 7-inch display, but it also weighs in at less than a pound. It does not run the BlackBerry OS, but is built instead on the QNX OS. It has 1GB of RAM, a dual-core processor, dual HD cameras, HD video recording, and HDMI output. The PlayBook is also quite versatile--able to play both Apple and Microsoft proprietary audio formats, and supporting both Adobe Flash and HTML5.HP WebOS SlatesDetails continue to leak out on two WebOS tablets codenamed Opal and Topaz. The Opal is a 7-inch tablet, while the Topaz is a more iPad-like 9-inch version. Based on leaked images, it appears that the tablets will have at least a front-facing camera, and a micro USB port.These HP tablets also have the advantage of running WebOS. Despite the fall of Palm, WebOS is actually a very capable mobile OS and possibly offers the most formidable challenge to iOS when it comes to a tablet UI. HP has a media event slated for February 9 where it is expected to announce details of these tablets.Apple iPad 2The iPad 2 starts with two distinct advantages over these rivals. First--there is already an iPad in existence and it has been a tremendous success. The culture is already established, and many companies are either already using the iPad, or are at least exploring the use of the Apple tablet for business. Second--because it is a second generation of an existing tablet, there is at least something tangible to measure it by, and a more concrete expectation that it will be available this spring based on Apple's standard annual product lifecycle.Speculation has been abundant on the iPad 2 since the original iPad launched. Given the general user feedback, and the features and functions the competition is bringing to the tablet arena, it is expected to have dual cameras, possibly a dual-core processor, a significant bump in RAM, and possibly a massive increase in the resolution of the display.Where does that leave us? Well, every device on this list is either vaporware or pure speculation at this point. Given the demand for the iPad, and the impending influx of tablets expected, it seems reasonable to believe that companies of Motorola, HP, Apple, and RIM's caliber can follow through and deliver sometime this year.For businesses looking to hop on board the tablet bandwagon, the decision between the various platforms will be driven largely by the existing infrastructure and culture. An organization that has BlackBerry Enterprise Server in place and relies mostly on BlackBerry smartphones is likely to choose the BlackBerry PlayBook, while a company that has already embraced the iPhone and\/or the original iPad would logically stick with the iOS platform.One large x-factor will be cost. The features and functions of a given device, or how well it meshes with the existing infrastructure may be trivial if the tablet ends up costing twice as much as its rivals. If you are in the market for a tablet right now, it seems that it will be worth at least waiting a month for more details--hopefully including launch dates and pricing--to emerge on these different tablet competitors.