If the character is at least level 60 before the boost, their primary professions and First Aid will be leveled up to rank 600. Other secondary professions will not be affected.
So skills like enchanting and tailoring will be upgraded. Professions like fishing and cooking however are not upgraded.
And from here
Characters who are already at or above level 60 will also have their existing primary professions and First Aid skill boosted to 600 skill level
That is even more clear
If you have no professions selected, they will be chosen for you. That depends on the type or armor you can wear:
- Plate: Blacksmithing and Mining
- Mail or Leather: Leatherworking and Skinning
- Cloth: Tailoring and Enchanting