Sarayana wrote:The guild bonus is 10%, but I can't recall what level the guild needs to get to. You also need to be revered with the guild to get your bonuses, if I'm not mistaken. Personally I wouldn't wait cause it's really not a hard grind, but it's up to you. Is your guild big enough to hit the leveling cap every week and level fast? Would you be focusing on this toon to gain rep with the guild?
You can summon Terokk every 15 minutes. And your break-down is spot on.

Well, knowing my current things as far as money and what not goes, I might not be playing Cata til as late as Christmas, depending on when I can actually get the expansion. By that point, at least, the Guild abilities will be available and the guild I have is fairly sizable. Combined with the fact that me and a few other guildies who won't have the expansion right off the bat will be doing guild runs of the older stuff for Guild Achievements as well, I'm fairly certain we could level up our guild fairly quickly.
Also, from what I've seen and heard, Mobile Banking is the only Guild Perk that requires you to have a certain rep to be able to use the ability. It's the special items and mounts that you would want to buy that requires the rep for your guild. From everything else I've seen, you gain those perks for just being in a guild of the appropriate level, meaning you can be in a guild that has the Perk Fast Track Rank 2 (10% Experience Buff) and have it from Lv 1 onwards.
Though if it's as easy as you say it is, I might just go and grind it up, but I tend to get bored easily and prefer the fastest way of doing things. The guild Perks would speed up the grind on my main considerably.