For the last few days I've been working to collect some of the new ore in WotLK so Krystella can start prospecting and cutting gems. For those of you who do not have mining... I fear you'll have some problems leveling up in the early weeks. Ore isn't exactly what I would call plentiful in the starting zones. What with three different professions requiring ore, I'd be surprised if there was much available on the auctions.
I'm not doing any quests or killing mobs so far, but I've scoped out the bulk of Howling Fjord and Borean Tundra and have gotten reasonably familiar with the ore spawns. The usual tactic of riding around the edges works fine in both places. The first time I went out during prime time - I saw 2 whole nodes. On my next outing I went back later in the evening and ore was more plentiful. I would equate Howling Fjord to Zangarmarsh and Borean Tundra to Nagrand in terms of spawn density.
When you first head out, you'll have no problem mining Cobalt Ore. I believe it was yellow to me (didn't write that down, Doh!) and I had no problem with failed attempts and such. So far I've seen no Saronite in either starting zone and WoWHead seems to agree with me on this. I did see a Rich Cobalt Node one time, but mostly they are regular. I was able to level all the way to 405 mining with no problem on Cobalt veins.
The next ore is Saronite, which was orange to me when I found it at 405. I also found some Rich Saronite nodes which I could not mine until 425 and a Titanium node which required 450. One thing to note: saronite was a challenge to mine while it was orange, I failed about 20-30% of the time. I would recommend taking some enchanted gloves whenever you plan to hunt up the higher ores to reduce frustration.
As expected the mineral veins drop the new "motes", also known as crystallized XX. So far my experience has been that cobalt drops water and earth, and saronite drops earth and shadow. I'm not high enough to try titanium yet, I just got to 425 earlier today. Even so, I'm tickled that the types of motes available through mining have been expanded and I'm curious to see what titanium will yield.
Bear in mind that any of this information could change before WotLK goes live, but so far I've been leveling mining fairly easily and collecting a good bit of ore for Jewelcrafting :)
UPDATE: Got my mining to 450 this morning - and automatically learned the new Mining buff (+500 HP).
UPDATE: Found my first titanium node over the weekend and received air/fire crystals from it.