I have written extensively on the differences between RomneyCare and ObamaCare. I've listed 13 differences between Mitt's plan and Obama's plan. I've written about how ObamaCare is a plan that benefits big unions and big businesses while RomneyCare really focuses on helping people. I have written about how Obama did not and could not have used Mitt Romney's health care plan when he created ObamaCare which gives further clarity into the differences between these two men's plans.
However, the best explanation of the differences between RomneyCare and ObamaCare is found at a blog called America Needs Mitt. The blog provides a nice visual chart that explains the differences between these two plans and supports his claims with footnotes. Here's the chart:
The chart along with the footnotes on the site is really impressive. I'm jealous and wish I had done this myself because it gives a nice side by side comparison of these two plans which helps to destroy the common claim that RomneyCare and ObamaCare are really similar.