Considering that this is one of those things that are virtually perfect for computer automation
You would think that but I've personally seen Turbotax screw up my taxes in years where I had a somewhat but not really complicated (by American standards) tax return. I can't speak for the rest of the World but in the United States your taxes are not a simple matter of mathematics. There's a logic flow involved, "Is X true? Proceed to Y." and at the end of the day if you can read the instructions you can do a better job of following the logic flow than Turbotax's programmers. It's my opinion that Turbotax is useless for anything more than 1040-EZ and if your taxes are so simplistic that you can file 1040-EZ why the hell would you pay someone else to do them for you?!
The year that Turbotax screwed up my return to the tune of $2,800 was the year that I stopped using it and started doing my taxes the "hard" way. It's not all that difficult, the hardest part is collecting the relevant information for your return and if you're enough of a geek to be reading Slashdot I assume you're enough of a geek to use some sort of financial management software. Moneydance is my personal favorite but even a well kept spreadsheet would work in a pinch. Once you have the data is simply a matter of knowing which form to file and going through it line by line. My Federal taxes take no more than two hours, my New York State taxes about three. The former can be electronically filed through Free Fillable Forms, the latter has to be done by mail, unfortunately, but most States are ahead of NYS here and provide an e-filing option for people who roll their own taxes.
Even if you outsource your taxes you're still on the hook for any errors or omissions, so what's the benefit to paying someone else to do them for you? Do them yourself, you'll save some money, learn a little bit about our tax system (and the absurdities therein) and be ultimately responsible for your own actions rather than trusting some other idiot's software to do the job for you. Of course, Americans aren't the sharpest knives in the drawer when it comes to taxes; how many people do you know that live paycheck-to-paycheck all year but get four digit refunds? A $2,000 refund is $38.46 per week that you could have had in your pocket if had bothered to fill out your W-4 properly.