The Palmdale Bulge went away... its quite controversial as seen here (from http://www.history.noaa.gov/stories/geod2.html):
One group contented that the historic leveling and
relevelings showed conclusively that the plateau
centered near Palmdale, CA had uplifted 10 to 16
inches. Another group eventually counter claimed
that the differences were due to instrument and
systematic errors resulting from observing
practices and atmospheric effects, especially
refraction.

Field tests made in the 1980's, showed that the
latter conclusions were correct. However, not
every one was convinced that was the case and
some hold to their original views even at this
date.