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There are some things that consumers can do in order to enjoy many of the benefits of HDTV movies without actually buying a Blu-ray player or an HD-DVD player. The most cost effective thing to do would probably be to buy an upconverting DVD player. This device plays standard definition DVD's and upconverts the video that comes from them so that it resembles HDTV resolutions. While an upconverted picture isn't as good as a real HDTV picture, it's significantly better than standard definition. This will also provide a way for you to breath new life into older DVD's.
Another option is to download movies in HDTV format. This can be accomplished through Microsoft's Xbox 360, the Apple TV, and several other devices. While the option of downloading High Def movies does circumvent having to use high def DVD's, it's not without its problems. In the case of the Apple TV, it can only get movies from iTunes, it only handles video with a resolution of up to 720p, and the picture that it produces at that resolution is quite grainy. The Xbox 360 doesn't really have problems with the quality of the picture, but the downloads can take extremely long times- sometimes upwards of an hour.
Another option comes in the form of the Vudu. The Vudu is a set top box that downloads video from the Internet and then upconverts the video to HDTV resolutions before displaying it on your TV. While this does eliminate the need for any kind of DVD, like upconverting DVD players, it produces a picture that's less than ideal because of the upconversion.
Another option still, is to get a high def DVD player that's part of another devices that you want anyway. For example, if you want the latest version of Sony's Play Station video game system, you'll get the built in Blu-ray disc player. In fact, there's no way not to get a Blu-ray disc player. If you already have Microsoft's Xbox 360, you can get an optional drive that will play HD-DVD's. If you want the video game system anyway, either of these two alternatives will probably cost you less than getting the video gaming system and a stand alone high def DVD player.
Whatever you decide, hopefully it should be helpful to know that there are alternatives to investing directly in high def DVD technology before you're ready.