Battlegrounds PvP, on the other hand, is more open and spontaneous, even in pre-formed groups. No classes or specs are shunned, and every player enjoys relative viability and success. Giving Arena points through Wintergrasp achieves two things: first, it opens up Arena rewards to people who do not participate in or have limited success in Arenas; second, it greatly incentivizes participation in Lake Wintergrasp. The only question left is the matter of Personal Ratings, which is a requirement for most of the current gear, a trend likely to continue in Wrath of the Lich King.
Granting both Honor and Arena points for World PvP is an interesting twist to an otherwise lackluster aspect of the game. One thing I mentioned in an analysis of Lake Wintergrasp was that it needed to be compelling enough for repeated participation, and awarding Arena points are a step towards that. Currently, the zone awards 150 Arena points for a win, along with substantial Honor. The rewards seem fairly large now (including 7500 Honor) but it's highly likely that the numbers will be tweaked and balanced before Wrath goes live. It's also important to note that Level 80 PvP rewards are also likely to cost substantially more points.
Arena points from Lake Wintergrasp is but a small step towards making World PvP compelling, however. Aside from Arena points, which is mere currency, there need to be equally appealing rewards that are only obtainable through the Battleground. These include, but shouldn't be limited to, titles and vanity gear. Putting gear that isn't necessarily optimal for PvE but appealing even for PvE players might be a good way to spark interest in a World PvP Battleground, such as vanity pets. There is no vanity pet obtainable through PvP, although I've often wished for one, maybe with an appropriate Arena rating requirement that doesn't decay through Seasons and appropriately high enough -- maybe 2100 -- to ensure rarity.
The important thing about the revelation of this reward mechanic is how open Blizzard is into exploring options for players. If these measures make it all the way through release, it means that players will have access to Arena gear without having to participate in rated Arena matches. It will also mean that Arena points can be calculated in real time, rather than weekly. It will be interesting to see how Blizzard will handle the conversion or carry-over of Arena points through Level 80 as well as the implementation of Arena Ratings outside of Arena play. With small details being put into the development of Lake Wintergrasp, I'm just a little more excited to see how it finally turns out when everything is finally in place.