The initial batch of K10 Barcelona processors will be for servers and some parts may later be released as Athlon FX socket 1207 parts in Q3 2007.
K10 processors for consumer PCs are expected to become available in the fourth quarter, but don't expect many of them as the real volume production is planned for early 2008.
However, there's a tiny snip of good news. The 2.5GHz K10 is rumoured to give the 3GHz Intel a run for its money.