Currently the Portage binpkgs are compressed with bzip2 which is CPU-intensive to unpack; given that other distributions (Mandriva, Fedora, SuSE) are well into using LZMA for the compression, it'd be a nice thing to be able to choose the compression method, and thus use, say, xv for compressing and decompressing the tarballs.
*** Bug 405891 has been marked as a duplicate of this bug. ***
*** This bug has been marked as a duplicate of bug 142579 ***