Collector's editions seem to be growing, in terms of both size and popularity, but is anyone actually buying these expensive and extravagant sets? Ars talks with David Riley from the NPD Group to see, and looks at the value of some of the upcoming collector's editions.http://arstechnica.com/gaming/news/2009/11/worth-the-money-the-gaming-collectors-edition-trend.arsOne of the lesser talked about developments this console generation has been the increase in the number—and size—of collector's editions available. At times it seems that nearly every game has some sort of special version, and major blockbusters feature extravagant and expensive add-ons that range from night vision goggles to batarangs. But do these sets actually drive sales? Ars spoke David Riley from the NPD group to find out."Limited and Collector's editions of games have seen a steady increase in sales over the years, particularly in this hardware generation," Riley told Ars. "At times, retailers work with publishers to provide exclusive bundles, which increases healthy competition and leaves consumers with more to choose from when looking for bundles that appeal to them."It's a gamble, but one that can pay off in spades," he added.But in addition to giving consumers choice by offering several different SKUs to select from, special editions also have the side effect of ensuring that the majority of customers will actually follow through with their preorders."It's not unusual for consumers to throw down the minimum payment on a preorder, end up not picking up the original preordered title and instead having that money applied to another preordered title," Riley explained. "Often times, collector's editions that are bundled with additional products are only available via pre-orders. This helps to better guarantee the consumer will honor the preorder...so, if consumers don't pick up the bundled preorder, they lose the chance to have a collector's edition of the title."And for brick-and-mortar retailers worried about the rise in prominence of digital distribution, it also helps provide an incentive for gamers to actually come into a store to purchase a game. But what exactly are we paying for? Here are three of the biggest collector's sets coming out over the holiday season:Call of Duty: Modern Warfare 2The just-released sequel to one of the biggest games of this generation, Modern Warfare 2, is undoubtedly going to be one of the best-selling games of the year. And it has a special edition to match its blockbuster status. The Prestige Edition of MW2 features an art book, a steel game case, a download code for the original Call of Duty, and, of course, a pair of fully-functioning night-vision goggles.Price on Amazon: $243.95God of War IIIThe Ultimate Edition of God of War III—which marks Kratos' debut on the PS3—comes packed in a replica of Pandora's box and features a limited edition art book. But it also gives buyers access to a wealth of digital content, including character skins, a combat arena, a franchise documentary, and two different soundtracks.Price on Amazon: $99.99DJ HeroRhythm games are expensive enough, but that didn't stop Activision from releasing a more costly version of its new title DJ Hero. The Renegade Edition features only a few improvements over the standard version of the game: an alternate color scheme for the turntable controller, a CD with tunes by Jay-Z and Eminem, and a hard carrying case that turns into a turntable stand. All for an extra $80.Price on Amazon: $199.99Uncharted 2: Among ThievesUnlike the rest of the sets on this list, the Fortune Hunter edition of Uncharted 2 wasn't actually available to purchase. Instead, the extremely limited edition was given away in various promos. It featured a replica of an ancient dagger, an art book, some downloadable content, and a special case signed by members of developer Naughty Dog. It is now available online for some absurdly high prices.Price on eBay: $2,000-4,000But is it worth it?Each of these bundles hopes that by giving you collectibles, art books, or content that provides some insight into the making of the game you'll pony up a few more dollars when you get to the register. They may start their lives as objects of geek lust, but the large boxes also make them easy targets for clearance when the buzz wears down. Legendary Editions of Halo 3 went on sale for less than the price of the normal game to clear out the space-consuming stock. To avoid similar embarrassments, collector's editions work best when they're truly limited. In the case of the Renegade Edition of DJ Hero, the turntables received a sparkly paintjob, the CD was mostly already-released material, and the stand worked just as well as your existing table or lap. Worth the additional outlay? Not really, although the packaging was nice.When it comes to Collector's Editions, ask yourself if the items are worth the extra money. Ask yourself if you'll care in six months. It also never hurts to wait for reviews. As the cost of creating games goes up, packing high-margin items in with games and then charging the premium is looking more and more attractive to publishers.