They aren't buffs, you have to keep in mind a lot of talents/glyphs are missing, for example the 40% Ghoul strength glyph, Rage of Rivendare, Obliterate damage et cetera. Everything is just being rescaled completely. After the patch is released, numbers will be adjusted further if needed and that is when you call them "buffs".
Its kinda wierd, mehhhh after Blizzard said pets won't be a big DPS factor like it is in cata and now they like buffing it ever more? i'm not following...
When did they say pets wouldn't be a big dps factor? Unholy always has had their pet as a significant portion of their damage.
Keep in mind that what you're seeing as a buff might not be a buff compared to live. It may be a nerf if scaling works differently, if weapon damage has gone up (and thus pets would be a lower proportion of your damage), or it might be to replace existing buffs on live that are missing in Mists.