  The rich wealth of observational data, and matching theoretical
investigations, of the transiting planet of HD209458 stands in sharp contrast
to systems for which only the radial velocity orbit is known. In this paper, I
summarize the current status of these observations, and motivate a variety of
projects that should be accessible with existing instruments. I describe
observational estimates of the planetary radius, and discuss the relevant
sources of uncertainty. I compare these estimates to those based on theoretical
structural models. This discussion motivates the observational pursuit of three
quantities that could be derived from measurements of the secondary eclipse:
These are the albedo, the temperature, and the orbital eccentricity. I review
the recent detection of the sodium D lines in the planetary atmosphere, and
discuss ongoing work to search for molecular features in the near infrared. I
also outline the use of the Rossiter effect to study the alignment of the orbit
with the stellar equatorial plane, and transit timing to search for additional
objects in the system.
