Not sure about Mandriva being a "killer" each to their own. KDE4, been using it for a while. first on Suse as a try out, and to be honest it really peed me off.
It comes as standard in Mandriva 2009 (my real world distro) which i installed recently so i decided to get stuck in. Once you get over the different way of working with the Plasma workspace, its actually very good, even with the widgets and the cashews
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It starts to become intuitive very quickly. Love the Dolphin file manager (no more konq) and the way it previews files.
Its the first incarnation of Mandy that i can actually say is point and click software. Even the PLF repos can be added from zarb.org with no more than a few clicks, no cut and paste into a root terminal, and of course all the stuff you really need is there. i.e, flash player, libdvdcss2, win-codecs etc.
Ah! rambling on a bit, i'll go now.
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