I had never heard that there was a difference before reading your comment, so I did a web search for "ubuntu font rendering", and most of the results are something like "How to fix Ubuntu's terrible, ugly, blurry font rendering." It's interesting how much people's preferences vary on this subject.
Is the patch that Legion refers to the same one that's in Ubuntu, or is that something else?
In what applications do you see a difference? I've spent some time looking quite closely at Firefox's font rendering in Fedora vs. Ubuntu and didn't notice any differences.
Comparing it to your patched F14 version, the roman typefaces look quite different, but overall I can't say I prefer one to the other. The italics, on the other hand, look much better in your version.
There is one strange thing in your F14 screenshot, though--the upper left of the lowercase letter 'a' is straight horizontal, rather than curving down as it does in all the other screenshots, both yours and mine.
Your Ubuntu screenshot looks very similar to your F14 screenshot, but not quite identical: see the dots on the lowercase i, and the above-mentioned problem with the lowercase a.
Personally I can't really tell the difference, but I'm guessing this is the patented hinting algorithm? If so, Fedora can't ship it, because Red Hat is a large US-based target with lots of money. However rpmfusion is available for those of us in the free world:
Is the patch that Legion refers to the same one that's in Ubuntu, or is that something else?
In what applications do you see a difference? I've spent some time looking quite closely at Firefox's font rendering in Fedora vs. Ubuntu and didn't notice any differences.