I am soul link spec and my felhunter has lost all of his base resistances too since yesterday. It should have 120 all resist base, +60 from Master Demonologist for a total of 180 like it was before.
When the devs are nerfing hunter pets, they're also affecting warlock pets for some reason as well. Nobody is complaining about being solo'd by a warlock pet, please correct their values to a more blizzlike value. My felhunter went as low as 40 dps the other day with FULL demonology spec.
http://wowmb.net/forums/f9/5303-pet_faq_freaks/According to this, with unholy power and master demonologist, my succubus should be doing 75 dps @ 2.0 attack speed (before armor reduction). However on Nostalrius my Succubus tooltip dps is only 54.