My company's SOP's state that an engine failure is definitely a Mayday Call. That is for many reasons some of which being: Unable to maintain altitude, what happens if you lose the other engine as well etc. For the Bus drivers, don't forget the RED LAND ASAP memo on the lower right corner of the E/WDisplay.
When it comes to TCAS RA's while you are on single engine, my company's QRH in the engine failure page, says to select the TCAS selector to TA's ONLY, so that not to be given RA's that you may not be able to follow.
I also believe that instead of starting Airbus Vs Boeing arguments it would be better to say well done to the guys that landed the plane safely and saved lives.