Sometimes, as seen in various apps' development cycles, throughout a radical change, there is, first, a removal of various features, shortly followed by a refreshed stack of functionalities, with the main purpose of replenishing the targeted app's look&feel.
Nautilus removed numerous features and, starting with the 3.5.4 version, introduced a fancy look (featuring monochrome icons, "full" toolbar, search-as-you-type, etc) packed with new features, oriented not only at replacing the "old" ones but creating an overall up-to-date file manager.