Where were the people up and screaming when Apple put Fast User Switching into their OS, "surely it will ruin Microsoft's Windows Software..."
Ideas are ideas, and implementations are implementations. If Konfabulator makes itself worth more then Dashboard, and remains worth the dollars that the developer charges for it, then people will buy it. Otherwise there are always new ideas which can be had and developed and sold to the computer nerds who need them.
If I was Launchbar (or my favorite,
Quicksilver) I would get my hands on the Spotlight SDK as fast as I can and figure out how to implement it to accomplish my goals. Apple has said what they will be offering, take that and improve on it, or take a different angle and try to do something else.
It's not like apple is coming out with a product release which will stomp all over your offering - they are giving you a good years warning! Take this time to improve your application and by the time Tiger comes out you will be able to kick the crap out of Spotlight or Dashboard or whatever.