  We present the discovery of 11 new double degenerate systems containing
extremely low-mass white dwarfs (ELM WDs). Our radial velocity observations
confirm that all of the targets have orbital periods $\leq$ 1 day. We perform
spectroscopic fits and provide a complete set of physical and binary
parameters. We review and compare recent evolutionary calculations and estimate
that the systematic uncertainty in our mass determinations due to differences
in the evolutionary models is small ($\approx$ 0.01 M$_{\odot}$). Five of the
new systems will merge due to gravitational wave radiation within a Hubble
time, bringing the total number of merger systems found in the ELM Survey to
38. We examine the ensemble properties of the current sample of ELM WD
binaries, including the period distribution as a function of effective
temperature, and the implications for the future evolution of these systems. We
also revisit the empirical boundaries of instability strip of ELM WDs and
identify new pulsating ELM WD candidates. Finally, we consider the kinematic
properties of our sample of ELM WDs and estimate that a significant fraction of
the WDs from the ELM Survey are members of the Galactic halo.
