One thing that probably factored in to the FOMC action is the pending quarter end. The guys I work with who cover fixed income, and particularly the money markets, have been talking about a new round of credit/liquidity issues as banks and funds dump holdings from their balance sheets ahead of the end of their fiscal quarter. This is something that always happens anyway (like mutual funds doing window dressing) but in an already tightish situation it is likely to exaserbate things.
I think it's pretty obvious that the market reaction was one which concerned itself with inflationary issues. Long rates rose, while short ones dropped, steepening the curve. Gold and Oil moved higher. The Dollar came under further pressure. The Fed did mention, if not harp on, inflation. They actually went back to a neutral stance after the rate move.
It's my job to watch the stock market, but even if it weren't, I'd be watching it closely over the next few weeks. That's the reaction I'll be curious to see. If the S&P keeps rallying as it has done, I would actually get worried.
Speaking to a couple of points made in this thread:
Splitlink: To your suggestion that the US "allow the Chinese to peg their currency at a low level", it's not like the US can force the Chinese to change the policy. That said, the fact that the US cut rates actually helps to make the current peg increasingly untenable for the Chinese. They are already having inflation pressures and being forced to raise rates (real interest rates in China are negative, which is encouraging stock market investment). As that rate differential widens, the currency pressure is going to build to an extreme. When that snaps, look out!
Atilla: Cutting government spending would serve the same fiscal purpose as increasing taxes (both reduce money supply). That said, how do you figure the US economy needs to be cooled down? It's already sluggish compared to the rest of the world.