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Depends entirely on the user. Anyone who says otherwise is probably selling something. For what I want on my personal machines, that is near bleeding edge packages, binary format, and things left near their vanilla state until the admin chooses otherwise, Arch has proven to be the best choice. Doesn't hurt that it has some of the best documentation of any distro out there either.
Others may prefer something less administratively intensive, or something more conservative, or maybe something with a wider community... and those are all valid choices too. More power to them. Edited 2012-10-22 19:01 UTC