The new skillset definitely seems like it would make Gladiator useful again. Just in terms of AoE tanking:

GLA gets

-Flash: AoE enmity generation and blind on 30 sec recast
-War Drum: the new AoE Phalanx on 60 sec recast

MRD gets

-Whirlwind: Most likely the new Storm's Path on 80 sec recast (ouch)

Both classes can use Rampart for the massive AoE hate spike, but only GLA can extend the defense bonus to other classes. Even if MRD still manages to hold hate via pure damage output, at least GLA can contribute with the passive defense bonus from Rampart and the blinds from Flash.

The more likely case is that in a typical Stronghold party, GLA will be the one holding hate at the start with Flash while MRD takes it in the end after Whirlwind because it seems like it will actually take some time to build 3k TP now.