I'll get on the TurboTax line too...
I went to school for accounting, and IMO, TurboTax has the best tax calculation functions, deduction finders, and the best handle on individual state laws. Plus it'll let you file online. For s's & g's a few years back I did my taxes with both TurboTax and Kiplinger, and TurboTax found a few more possible deductions, and gave me a total savings of almost $300 in taxes over what Kiplinger came up with.
Intuit has become the master at financial apps. I use Quicken2001 at home, and my company uses QuickBooks for about 25 subsidiaries. They are usually right on track in regards to tax law and all that jazz.
Plus it's about the same cost as Kiplinger is.