According to Softpedia, the next version of Lubuntu, the LXDE-based variant of Ubuntu, will feature the Lubuntu Software Center, a user-friendly package management tool modeled after the one in the main edition of Ubuntu. The link below includes instructions for how to install the Lubuntu Software Center from the Lubuntu Desktop PPA, if you are inclined to test beta software.
http://news.softpedia.com/news/Introducing-Lubuntu-Software-Center-221531.shtml