Yeah, Rumours has been re-released before more than once. I personally have it in LP format, CD, MP3, DVD-A, and the 2-disc reissue from a few years ago. So, besides being an obsessive hardcore, why am I shelling out over $80 for the Rumours Deluxe Edition?
Because it is deluxe indeed! It not only has an LP, Rumours CD, and the outtakes CD I'd heard before, but it also has another outtakes CD that I hadn't heard before which includes treats like Stevie's early version of "The Chain" with different lyrics as well as Christine's "Keep Me There" which would be blended into hers to make "The Chain" we know and love today. Lindsey has a cool early version of "Go Your Own Way" with the lyric "You can roll like thunder." Additionally, it has a live CD from the Rumours tour and finally, the 1976 Rosebud documentary DVD in high quality. With regard to packaging, the large booklet and gatefold framing is beautiful. Hardcores must have this!
You can buy it from Amazon and similar stores, or you can get it bundled with T-shirts and posters from Fleetwood Mac's official site.
Note: There is also an Expanded Edition version available with only three CDs; it's cheaper, but also doesn't include the Rosebud DVD, the LP, or as many outtakes (although the outtakes that are missing seem to be the ones from the reissue a little while ago - something to keep in mind if you're trying to save money). I say go for the super-deluxe but that's just me.