  We present preliminary results on the properties of relativistically
broadened Fe K-alpha lines in a collection of more then 100 Active Galactic
Nuclei (AGN) observed by the XMM-Newton EPIC-pn camera. Our main conclusions
can be summarized as follows: a) we detect broad lines in about 25% of the
sample objects. This fraction increases to 42+/-13% if we consider only objects
with more than 10000 counts in the hard (2-10 keV) band, and to 50+/-32% for
the small sub-sample (6 objects) of type~1 Piccinotti AGN with optimal
XMM-Newton exposure (at least 200000 counts in the hard band); b) we find no
significant difference in the detection rate of broad lines between obscured
and unobscured AGN; c) the strongest relativistic profiles are measured in
low-luminosity (< 10^43 erg/s) AGN; d) Equivalent Widths (EWs) associated with
relativistic profiles in stacked spectra are ~150 eV for all luminosity
classes; e) models of relativistically broadened iron line profiles ("kyrline",
Dovciak et al. 2005), which include full relativistic treatment of the
accretion disk emission around a Kerr black hole in the strong gravity regime,
yield an average disk inclination angle ~30 degrees, and a radial dependence of
the disk emissivity profile ~-3. The distribution of EW is very broad, with
<log (EW)>=2.4. We estimate that an investment of about 1 Ms of XMM-Newton time
would be required to put these results on a sound statistical basis.
