--- SCREENSHOTS ---
Eastern Kingdoms
Kalimdor
Outland
--- INFO ---
Since there have numerous requests for these and I wanted them back myself, while I was reinstalling WoW on my PC, before I updated to TBC I grabbed the old loading screens out of the data files. While I was digging around, I found the loading screen that I think was used in the beta and made that the Outland loading screen. That's the good news - now on to the bad news.
Since the Burning Crusade loading screens are contained in a patch file already (locale-enUS.MPQ) a simple copy of the MPQ containing these screens and running ModelEditFix won't work. Instead, you'll need to open your locale MPQ file (locale-enUS.MPQ for me, will vary depending on your country) and replace the current loading screens with the old ones. The loading screens should reside in /Interface/Glues/LoadingScreens/. I'm unsure how to do this on Windows, but I think MyWarcraftStudio and MPQEdit will allow you to do this. On Mac OS X, I used MPQ Extractor and DropMPQ to get the job done.
--- DOWNLOAD ---
http://iindigo3d.com/wow/loadingscreens.zip
Enjoy!