  The Casimir effect between metal surfaces has now been well-verified at the
few-percent level experimentally. However, the temperature dependence has never
been observed in the laboratory, since all experiments are conducted at room
temperature. The temperature dependence for the related Casimir-Polder force
between an atom and a bulk material has, in contrast, been observed between a
BEC and a silica substrate, with the environment and the silica held at
different temperatures. There is a controversy about the temperature dependence
for the force between metals, having to do with the magnitude of the linear
temperature term for both low and high temperature, the latter being most
prominent at large distances. There are also related anomalies pertaining to
semiconductors. The status of this controversy, and of the relevant
experiments, are reviewed in this report.
