  We apply the new-generation ARPES methodology to the most widely studied
cuprate superconductor YBCO. Considering the nodal direction, we found
noticeable renormalization effects known as "kinks" both in the quasiparticle
dispersion and scattering rate, the bilayer splitting and evidence for strong
interband scattering -- all the characteristic features of the nodal
quasiparticles detected earlier in BSCCO. The typical energy scale and the
doping dependence of the "kinks" clearly point to their intimate relation with
the spin-1 resonance seen in the neutron scattering experiments. Our findings
strongly suggest a universality of the electron dynamics in the bilayer
superconducting cuprates and a dominating role of the spin-fluctuations in the
formation of the quasiparticles along the nodal direction.
