Really, I am. The quote from my previous post about the 1.0 release of Live Writer said:
We have heard from many of you about the pain and frustration in the last beta release when support for installing on x64 systems was not supported. We're happy to share that this has also been fixed and now installation on Windows Vista x64 is fully supported.
When I read this, I did wonder whether not mentioning XP 64 bit was intentional or not. It turns out that it was. The full Live Writer release does not work on XP 64 bit.