Have used H&RB's TaxCut for many many years. This year branded just as H&R Block 2009. No issues here, and generally happy. Online reviews have as almost a tie with Turbo Tax. Can't go wrong with either. Just get the type\level that best handles your income tax situation (eg. Basic, Deluxe, etc.)
I don't mean to overstep the line but can't resist commenting on your situation Mark K - if the right figures were entered in the right fields, that program should have calculated correctly, unless the field entries were manually overridden or incomplete info was provided. Further, at the end of the return Taxcut does a check and issues cautions and warnings to check before proceeding to file. If that happened and they were ignored not nice things could result if the return is filed. My point - if in fact entries were correct in the right fields and the program did not calculate correctly, then you should have a valid software liability claim to pursue with H&R Block (to recover any costs and penalties incurred as a result of the error), which I would have done. I'm sorry your mom had the experience that she did. Hope she has better luck in the future.