UMPlayer - The Universal Media Player, is an application based on SMPlayer 0.6.9 created by Ori Rejwan, with some extra features like Youtube playback.
But now the UMPlayer project seems dead (no changes since December 2011), Youtube doesn't work anymore and some people asked the SMPlayer team to fix UMPlayer. So we made this release.
However we recommend to use SMPlayer instead. It includes most of the features in UMPlayer, like support for Youtube and skins, plus some other features that have been recently added and that are not available in UMPlayer, so if you're an user of UMPlayer it's highly recommended to migrate to SMPlayer.