This is just one more way that Blizzard is aggressively attempting to reverse the subscriber bleed that only just recently came to a halt. Lowering the barrier to reentry for returning players will go a long way toward getting those people to check back in, especially if it means those players will get to see the other faction for the very first time. It could very well mean a brand new gaming experience for some of those returning players.
The new Scroll of Resurrection would also explain the level 80 armor sets that were datamined on the patch 4.3 PTR. Boosting a character from level 12 to level 80 wouldn't be all that useful if that character were still using level 12 gear. Receiving a full set of level 80 gear in the mail after your boost would solve that little problem.
We assume you'll also get the spectral mounts included in the aforementioned teasers, possibly as a perk for the one doing the recruiting rather than for the recruited. Images of both of the spectral mounts are below if you're interested in that sort of thing.
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