One of the most annoying things on Linux was the default set of fonts. More specifically, there was nothing comparable with the usual (and ubiquitus) fonts found on Windows like Arial, Times New Roman, etc.
Web pages, documents from MS office and everything polluted with those fonts were not properly rendering in the Linux applications.
Now, Red Hat decided to do something to fix this and released a first version of a set of fonts with the same metric, so that a replacementis perfectly usable.
For more info on the press release
the package review request was just completed. Expect to find them with a "yum install liberation-fonts" real soon now