User blog comment:Commdor/More ME3 Details from the BioWare Forums/@comment-2174252-20110421145516/@comment-2174252-20110421152041

The following is the Spanish script where the "melee class" is mentioned:

"- Nuevas habilidades para Shepard: lanzarse en busca de coberturas a lo Max Payne, rodar, saltar pequeños huecos en el suelo, girar como los SWAT y golpear al enemigo con mayor variedad de ataques cuerpo a cuerpo. Se menciona específicamente "una nueva clase: Heavy Melee" que aproveche estas capacidades de combate."

Translated; "It's specifically mentioned 'a new class: Heavy Melee' which take advantage of these combat skills"

From my view, it doesn't clearly specify if "Heavy Melee" is whole new class or part of a skill tree.