The group is humming right along, they are level 51 and about a third of the way to their next level. While it is my desire to get them to 58 as soon as I can, I admit I have not been leveling as efficiently as I can. I got wrapped up in the "Zelda tribute" quest line, which ends with a battle against a level 56 elite (who happens to hit very hard and has a knockback attack). The rewards are of very limited use to the group, but once I started the quest I decided I would finish it, which slowed my leveling pace because it requires you to run all over the place.
There are many other quests that I can still complete in Un'Goro Crater, but many of them are collection quests, and with more and more options for questing I am skipping collection quests when I can. And many of the ones in Un'Goro have poor drop rates, as well (or at least they used to, and I'm no longer interested in figuring out if that is the case or not).
I got about a level's worth of experience thanks to the special bonfire events going on in the game. You get just under 3% of a level for doing a very quick quest at the bonfire camps outside of most of your faction's quest hubs. You also get about 6% of a level if you "desecrate" the opposing faction's bonfire. This is a lot of experience for nothing more than clicking on an NPC or item and clicking "Complete." Desecrating an opposing faction's bonfire flags you for PvP if you are on a PvE server. But there seemed to be very little ganking on Eldre'Thalas. In any event, not wanting to do even more running around, I limited my 'desecrating' to the fires in Gadgetzan and Winterspring, since the Alliance bonfires were within a short distance from the Horde bonfires.
Aside from an easy way to stockpile experience, the only other effect was to leave the pets a bit farther behind than normal, since they only gain experience from kills. But it didn't take long to rectify that, and they're level 51 now as well. The scorpid was replaced by a gorilla. Now that I can use the talents that increase happiness during combat, it's a simple case of taming the pet and having him fight two or three battles, and it is at max (or near max) happiness. No need to worry about feeding them even a single time.
Anyway, while there are still plenty of quests in Un'Goro, I've already visited the Bulwark in Tirisfal Glades and grabbed the first few Plaguelands quests. There are a fair number of quests that do not require you to collect a lot of dropped items, and therefore some of the tedium from grinding can be avoided. Plus, it gets me back to doing quests that are a bit more challenging, as some of the Un'Goro quests were already green. And frankly, I have not done the Plaguelands quests all that often, and so they're actually a bit fresh.
But my goal is still to get through the next seven levels quickly and then head to Outland. The questing in Outland is more straightforward from a gear-collecting standpoint, particularly at the beginning (after which it gets somewhat muddled again, sigh). From there it's just a steady quest grind towards level 68 and Northrend, but that's a bridge for another day.