  The discovery of the first gravitationally redshifted spectral line from a
neutron star (NS) by Cottam, Paerels and Mendez has triggered theoretical
studies of the physics of atomic line formation in NS atmospheres. Chang,
Bildsten and Wasserman showed that the hydrogenic Fe H$\alpha$ line formed
above the photosphere of a bursting NS is intrinsically broad. We now include
rotational broadening within general relativity and compare the resulting
profile to that observed during Type I bursts from EXO 0748-676. We show that
the fine structure splitting of the line precludes a meaningful constraint on
the radius. Our fitting of the data show that the line forming Fe column is
${\rm log}_{10} (N_{\rm Fe, n=2}/{\rm cm^{-2}})=17.9_{-0.42}^{+0.27}$ and
gravitational redshift $1+z =1.345_{-0.008}^{+0.005}$ with 95% confidence. We
calculate the detectability of this spectral feature for a large range of spins
and inclinations assuming that the emission comes from the entire surface. We
find that at 300 (600) Hz only 10-20% (5-10%) of NSs would have spectral
features as deep as that seen in EXO 0748-676.
