You are not alone. Kubuntu users in general would agree that Kubuntu does not
get the same care and attention that Ubuntu does from Canonical. The reason is
that Ubuntu has a close relationship with Gnome and their futures are tied
together, each sharing a great deal of history and owing a lot to the other.
Without Ubuntu, Gnome would not be so popular and maybe the reverse is true as
well. It is by far the biggest distro to use Gnome. KDE on the other hand is
more widespread and it does not have the same close ties. Kubuntu developers
complain all the time that they do not have the same resources, while Canonical
denies this and says the projects are separate entities which set their own
objectives.

You can install KDE instead of Kubuntu. This gives you full KDE on top of the
Ubuntu base which is somewhat different from Kubuntu which gives you only what
the Kubuntu project wants to install. If you try to do this, Synaptic will try
to remove Kubuntu in which case you lose the Kubuntu themes, splash screens,
sounds, icons, etc. I don't advise this, but just point out that it is possible
to run KDE and still use the repositories to get the benefits of using
Canonical's repositories which are huge and still run KDE based on the same core
as Ubuntu.

The problem that many users have with Ubuntu/ Kubuntu and its development cycle
is that it works at first and suddenly things may start to go wrong. This
happens because the release is based on one version of Gnome or KDE, but then a
new version is released by Gnome or KDE, independently of Ubuntu or Kubuntu and
then we get lots of updates.

The development cycle that Canonical sets is not synced with the other projects
and this leads to a development cycle within a development cycle which is one of
the reasons that Shuttleworth wanted to sync
development schedules so that an Ubuntu release would coincide with a
new Xorg and new Gnome release. So far, nobody has taken him up on it and many
critics see this as self serving. It is only a matter of time before schedules
begin to align on their own. Now lots of distros have annual or semi-annual
releases. The pressure will mount on the Gnome and KDE projects to get in step
or risk losing their users.

Just my take on it. There is lots being said about this in the RSS feeds,
Brainstorm and forums if you care to wade in on the debate.