Either way, it strikes me that newcomers and casual gamers just now hitting 70 must be having a terrible time in PvP. They sign up for their first matches with their mix of greens and blues, and find themselves like a mouse before lions, with every opponent decked out in the kind of gear they only dream of attaining. Even if they really want to, is there any chance for them to learn how to PvP when they get killed in just a few seconds? Furthermore, even if they have the dedication for it, they may feel like leech on their team, kind of like a level 61 player in Alterac Valley, who knows all to well that he or she can't really contribute that much -- except the newcomer to level 70 is already at the level cap. The only way they can improve at PvP is to somehow get matched up with good enough teams to carry them trough many many battles until they finally have enough points to buy some good gear. If not, they get virtually nil from losing all the time no matter which battleground they join. Of course they may keep losing at the Arenas for a few months until they finally accumulate enough points to buy a few pieces of gear, but in the meantime their opponents are winning and saving up points a lot faster than they are.
If there's no way to shape up, can they only ship out? Are the doors of entry into end-game PvP completely shut off in the face of newcomers? If such a person came to me asking what they should do, I could only suggest they try to maintain a positive attitude, keep doing their best, and possibly get new gear from PvE as much as they can. I might also remind them that another expansion is coming next year, which should level the playing field. How would you advise a new level 70 to get into PvP?