  The WiggleZ Dark Energy Survey is a large-scale structure survey of
intermediate-redshift UV-selected emission-line galaxies scheduled to cover
1000 sq deg, spanning a broad redshift range 0.2 < z < 1.0. The main scientific
goal of the survey is the measurement of baryon acoustic oscillations (BAO) in
the galaxy clustering pattern at a significantly higher redshift than previous
studies. The BAO may be applied as a standard cosmological ruler to constrain
dark energy models. Based on the first 20% of the dataset, we present initial
results concerning the small-scale clustering of the WiggleZ targets, together
with survey forecasts. The WiggleZ galaxy population possesses a clustering
length r_0 = 4.40 +/- 0.12 Mpc/h, which is significantly larger than z=0
UV-selected samples, with a slope gamma = 1.92 +/- 0.08. This clustering length
is comparable to z=3 Lyman Break Galaxies with similar UV luminosities. The
full survey, scheduled for completion in 2010, will map an effective volume
V_eff ~ 1 Gpc^3 (evaluated at a scale k = 0.15 h/Mpc) and will measure the
angular-diameter distance and Hubble expansion rates in three redshift bins
with accuracies ~ 5%. We will determine the value of a constant dark energy
equation-of-state parameter, w, with a higher precision than existing
supernovae observations using an entirely independent technique. The WiggleZ
and supernovae measurements lie in highly complementary directions in the plane
of w and the matter density Omega_m. The forecast using the full combination of
WiggleZ, supernovae and CMB datasets is a marginalized error sigma(w) = 0.07,
providing a robust and precise measurement of the properties of dark energy
including cross-checking of systematic errors.
