For instance there is a Sun Java installer that "just works" with Ubuntu and will keep your Sun Java up to date when you do your system updates. If you need a Bit Torrent client you can just
apt-get install transmission
but it turns out to be quite an exercise to compile and install any Bit Torrent client for Red Hat Linux.
I remember how Solaris was the center of the open source world in 1991, but by 2001 it was starting to get hard to compile things on Solaris. Red Hat is also diverging from the open source mainstream and it is "just hard" to do things that "just work" with Ubuntu.