Now consider the
actual usefulness of such a
contraption. A
terminal is used for a lot of
text input and
output. Making the
background transparent will just confuse your
brain and
fatigue your
eyes(
especially if your wallpaper is extra flashy). Transparent terminal is just an
eye candy. Now change it back to something
readable and go back to
work.
If it's making you happy - by all means use it.