You've got options...
There are a number of different options for you.
The first answer should not involve you purchasing any hardware. If you want to, you should be able to purchase "Plex" on the
Google TV app store for 99 cents. You then
download the Plex Media Server (PMS) onto your MacBook. Point the PMS to the location(s) you keep your video files (and music). Then setup the Plex app on the Revue to point to the PMS server on your MacBook. If your video files are not in the proper format to play on the Revue, the PMS will transcode (convert) the video on-the-fly to a format the Revue can handle. Keep in mind that this will require a fair amount of processing power in the background. But the benefit is that this will allow you to stream a much broader range of video files than the Apple TV can natively handle. I don't have personal experience using the Logitech Revue, but I know it works on the Sony NSZ-GT1.
The second answer, much as Raz0rEdge just mentioned, is that you can place movies on your MacBook into iTunes and you can then stream those files to the AppleTV and on to your TV. The negative of this option is that the AppleTV only accepts a few formats and if your files are not in the correct format, you will need to go through the often time consuming process of putting them into the correct format through programs like Handbrake.
The third option (the one that I choose) requires (as of now) the use of an iOS device. It can be an iPhone, iPad or iPod Touch (more recent the better). You purchase the
Plex app or
Air Video (those are two of the better ones) on the App Store. These programs are very similar and work the same was as I described using the Logitech Revue (just swapping out the Revue for the Apple TV in this case). The difference is that the video is *first* sent to the iOS device (iPhone, iPad, iPod Touch). From that point, you can redirect the video using the
AirPlay feature in iOS straight to your Apple TV. It's works really well as long as you have some reasonably recent hardware to run the Plex Media Server or the Air Video Server (both server apps are free for your MacBook). When the next version of OS X (Mountain Lion) comes out, AirPlay will be
baked right in at the OS level. That should even eliminate the need for the iOS device.
My advice? Go with option 1 first. You already have everything you need with the exception of a 99 cent application. If that works and you want more functionality, consider option 3. AirPlay is a incredible feature and most people don't really get how versatile it is. There's very little you CAN'T stream onto the Apple TV, but all anyone seems to focus on are the few apps on the device itself. The key to the Apple TV is AirPlay.
Good luck.