It's a market reason. 98% of all computers on the web run some version of Windows and IE. Hackers generally don't waste their time for the 2% that use Mac, Firefox, Safari, etc......
IE has always had it's problems but I'm not convinced Firefox is MUCH more secure. Granted they didn't have the active X problems IE did but I really thought it was market share issue, so to speak. Just my opinion.
People who think they are 100% or 95% safe with the non-ms stuff may be a bit naiive.
We'll see over time.
