Well, I trade to make money and don't mind paying taxes on my gains. Now that's not to say I don't have some POS losers in my portfolio that I won't sell, but like I said, to sell a potential huge winner with great news pending for tax loss defeats my purpose of investing in the market (making money).
This very well could be the 'one year' folks will not want to offset losses because the Bush Tax cuts (are favorable on capital gains in 2010 still). These will expire end of the year, concerns that they will not be extended in 2011 and beyond.
Thus, it may be more advantageous to 'postpone' taking losses in 2010 and take them in 2011 where the taxpayer could be in a higher tax bracket (especially resulting from capital gains) and 'save more' on taxes in 2011 then they could in 2010.