Microsoft will release the final version of Internet Explorer 9 at the SXSW conference on March 14. This information tallies nicely with what we already know: Microsoft has said that there will only be one RC, and March 14 very nearly fits the six-week release cycle that Internet Explorer has so far stuck to.
IE 9 on SXSW
The South by Southwest (SXSW) Conferences & Festivals offer the unique convergence of original music, independent films, and emerging technologies. Most importantly, though, the IE team is holding a party at SXSW.
Microsoft has already said that the RC will automatically update to the final version, but we're not sure whether a switch will be flipped at the SXSW party, or if we'll have to wait for the next Patch Tuesday. Either way, a direct download should be made available around 9pm on March 14.