- 60-62: The gear you will get in this level range is comparable to MC gear, minus the set bonuses. This includes quest rewards and instance drops. (And an awesome trinket from the Zangarmarsh field scout NPC who has pvp rewards. I believe its 33 magic dmg, and chance on spell hit to restore 150ish mana).
- 63-67: At this level range, the gear that everyone will be getting starts to match closer to BWL status or better, again, minus the set bonuses.
- 68-70: This is really where you can start picking up some of the nice initial expansion gear. There is some really nice gear to be had from Karazhan if you can muster a very organized 10 man force and tackle the challenges that this instance provides. (And yes, some of the boss fights are very, very hard. It's great 8)
The instances are very very well done. In nearly each of the new zones, there is a winged dungeon (think Dire Maul). There are generally three 5-man wings with different difficulties, and one raid wing per dungeon. My favorite of them all up to this point would either have to be Auchindoun in Terokkar Forest, or Tempest Keep in The Netherstorm. Why is this design so great? Each instance is relatively short in comparison to the instances we "grew up" with. No more 5 hour scholomance or stratholme clearings. Each 5-man wing takes anywhere from 25 minutes to 1 hour to do, depending on how good or bad your group is. Also, each instance generally has 2-3 bosses per wing. This way you can go straight to the instance you need that has the loot you are after. No more clearing through 8 bosses to get to the only 1 that you need.
In addition, there is a "heroic" difficulty mode that the group leader can set for each of these instances. This raises the mobs levels to 70, increases their damage, hp, and armor a lot. During these runs, the bosses drop better, higher level loot, in addition to tokens that you can collect and turn in at an NPC in Shattrath city for level 70 casual epic rewards. Some of the rewards are decent, and some of them are pretty damn nice. To clarify, everyone in the group can pick up the tokens, so you don't have to worry about ninja looters for those. This way, everyone gets something out of the instance. Some bosses drop more tokens than other, I'm guessing based on overall difficulty. All-in-all, it will take roughly 8-10 heroic instance runs to get a nice level 70 epic trinket/shield/offhand item/etc with the current token drop rate. Not bad at all, considering each instance also drops pretty nice level 70 blues along the way.
Also, the exp gain in a good 5 man instance is by far the best exp/hr you can gain. I was getting roughly 1.1k exp per mob in a 5 man party @ around level 61. Keep in mind it takes about 500k exp to go from 60-61, and you can tack on about 80k exp for every level after that. Solo outdoor mobs give about 500 exp per kill solo, and quest turn ins generally give about 7-8k. It takes over 1 million xp to go from 69-70. You are looking at 6-7 weeks to go from 60-70 for the super casual, a little over a month for your average wow junkie, and 2 weeks for the hardcore. (But you're all hardcore, right? :P)
All being said and done, when I transfered to the alpha, I was using mostly BWL gear (I quit raiding on this toon as of January of this year, 11 months ago), with my exalted AV rewards, ZHC from ZG, and now that I'm 70, I think I only kept 3/8 nemesis (belt, legs, bracer) on mostly because of the ZG enchant I have on the nem pants, and the 23 dmg set bonus. This is also because I was an idiot and vendored the quest reward pants I got for doing the Blood Furnace (the 2nd instance you will run in hellfire peninsula), because they buffed them to be better sometime during the alpha. :( Oopse. Oh well. They were better than nemesis pants. I think something like 30 stam/20int/33 dmg/22 crit rating (1.5% @ 60). Damnit. The rest of the loot, including trinkets and jewelry, was an upgrade.