i never really got to experience the pvp in the beta. i got to the pvp zones, but there were no heroes to fight.
apparently there are FFA zones (villains vs villains, heroes vs heroes, villains vs heroes, etc) too, which could be quite fun. they introduced the arena a while back too, which i've also not ever had a chance to 'play'. afaik, they are instanced zones, much like the rest of CoH
there are 5 new archetypes too, which aren't directly comparable to their CoH counterparts.
Dominators, get control powers primary and also damage secondaries, after a certain number of attacks they can release 'domination' which increases their damage (by up to double i think) and the strength of their control powers. Similar to Controllers, but with much more damage output, and no need to heal!
Masterminds get Henchmen (Robots, Ninja, Soldiers or Zombies), and a series of buff secondaries. pretty powerful, because they can have i think 6 pets as well as themself with some attack powers.
Brutes are Melee primaries with defense secondaries, but much higher damage (and lower defense) than a tanker and they gain 'rage' during a fight so they hit for more the longer they are fighting.
Stalkers get again, melee primaries, but they also get 'assassin strikes', which deal 7x the normal damage or something ridiculous, and must be performed from 'Hide', the first power in any of their 'defense' secondaries. Their powers are similar to Scrappers, but again very different.
Corruptors are damage primaries with buff secondaries. Similar in terms of damage and powers to Blasters, but much crappier healers than a Defender.
theres also a few new powersets, and some fun new missions (i love robbing them banks!). no new travel powers yet.
edit: also, CoV is a standalone. you dont need CoH to play it (but then you cant make heroes, have only 8 char slots instead of 12). once you 'upgrade' your CoH account to CoV, you are (in PLAYNC's eyes) paying for 2 games for the price of 1 (which doesnt sound like a big deal, considering its an expansion) at £8.99/month
i don't have a sig.