For those of you wondering, the new bag patterns can be purchased in Silithus. Or at least some of them can. The good news is that the enchanting bag pattern can be purchased by any character and traded to a tailor. Here’s a picture of it.
20 Slot Enchanting Bag
I didn't find a pattern for a 24 slot bag.
The bad news, or at least I see it as such, is that tailors have to have the right reputation to buy the herbalism bag patterns. The patterns are bind on pickup.
20 Slot Herb Bag
24 Slot Herb Bag
It’ll be a long time before my level 42 priest will have enough reputation to purchase those, so I guess I’ll be buying my herbalism bags instead of making them. Of course, I won’t buy them in the foreseeable future. Prices will be outrageous for some time to come.
Tailors might also wish to note that these bags are bind on equip.