I had to play around with these commands on my Mac as well. The following two commands work for me, assuming the sdk folder is sitting right on the first level of your mac hd and bootanimation.zip is sitting in the tools folder with adb. If not, just alter the paths.
Keep in mind you can drag and drop into Terminal to make things easy. For instance, the first time I ran this i typed "cd " then dragged the Tools folder over, it inserts the path, especially useful when buried deep (like your desktop).
/android-sdk-mac_86/tools/adb push bootanimation.zip /data/local
**also, the big difference I noticed from other posted directions was that in the 2nd command I had to give the path to adb, even though I had changed directory in the previous command. Wouldn't work otherwise. Perhaps a Mac terminal expert can comment on why**