Multiple Crafts on 1 Character
Nothing has happened to it. In the past, you had raised 3 crafting skills but only had 2 “learned” at any given time. You could go to that third crafting trainer and swap it out for a bit of silver.
That is still how it works. Now, however, ANet has added something where you can have 3 “learned” crafting skills at a time. It can save you a bit of money in that regard.
You can have every crafting on one character if you want. You would have to pay to switch is all and the gem store item allows you to have 3 active ones instead of 2.
So, your jewelry crafting is still there. No change.