Here's a fix for the broken link when updating to the latest (speech recognition) version of Live Search. Just add an extra "Live Search" folder and copy and paste. Works like a charm for me.
Compliments of smeg36 at sprintusers.com:
Solution Found: My initial theory of the file path was correct. I reinstalled the original version, which works with the today plugin, and found the path the plugin looks for is Program Files/Live Search/Live Search/Live Search.exe (the space in the name is very important). When you install the new version the program is renamed LiveSearch.exe, and is placed in Program Files/Live Search, omitting the .exe from the second Live Search folder.
So all you have to do if cut and paste all the files in Program Files/Live Search into Program Files/Live Search/Live Search, and rename the .exe from LiveSearch.exe to Live Search.exe. Simple really. That fixes the problem until either HTC/Sprint release a ROM with the newer program working, or someone figures out the registry to change the icons/programs ran. Now I need to figure out how to get the Music icon to open WMP. My best bet is probably to rename WMP's .exe to the Music Store program. I just need to figure out the path used by the plugin to launch the Music Store.