  The ultra-relativistic heavy-ion program at RHIC has shown that at
intermediate transverse momenta ($p_T \simeq 2$-6 GeV) standard (independent)
parton fragmentation can neither describe the observed baryon-to-meson ratios
nor the empirical scaling of the hadronic elliptic flow ($v_2$) according to
the number of valence quarks. Both aspects find instead a natural explanation
in a coalescence plus fragmentation approach to hadronization. After a brief
review of the main results for light quarks, we focus on heavy quarks showing
that a combined fragmentation and quark-coalescence framework is relevant also
here. Moreover, within relativistic Langevin simulations we find evidence for
the importance of heavy-light resonances in the Quark-Gluon Plasma (QGP) to
explain the strong energy loss and collective flow of heavy-quark spectra as
inferred from non-photonic electron observables. Such heavy-light resonances
can pave the way to a unified understanding of the microscopic structure of the
QGP and its subsequent hadronization by coalescence.
