For all the nitpicking about Flagpole's original post, he's spot on if you're an investor (or potential investor) with a long-term horizon. While there are signs that the market might go south again in 2009--including a looming crisis in the commericial real estate market, poor financial statements as large companies complete their write-downs of losses from investments in bundled mortgage securities and other gambles, increasing awareness of a "second wave" of mortgage instrument failures due in 1-2 years, and a potential spike in energy costs as OPEC and other oil-rich countries seek to control ouput--the MAIN point of his post is: get in the market if you're not going to get out for at least 5-10 years. Smaller, patient investors can reap the benefits of larger investors' movement to bonds and other "safe" holdings in the interim; once they move back into the market, smaller, more agile investors stand to benefit, long term, as indices rise with economic recovery.
I'm not a big believer in timing the markets, either. One, I'm not smart enough, and two, I'm too busy to try and overcome that. But we've maxed out our 401k contributions--thank goodness my wife still has a matching employer!--because retirement is decades away.
Good luck to everyone.