It didn't get a "HUGE" buff, they just changed it.
The way I play Udyr now is different, but not by much. Normally, I'd go with Locket/Omen and then even more defensive items, but because they nerfed the damage to Phoenix, I decided to try a different build.
Cloth armor + 5 health pots
Madreds Razor
Boots
Heart of Gold
Merc treads
After this, I aim for Madreds Bloodrazor. So right now, I have the following
Merc Treads
Madreds Bloodrazor
Heart of Gold
Depending on what they have, I will build accordingly. Normally, I'd go or something that has health so...depending on their setup, I'll aim for Banshee's Veil or Sunfire Cape.
Everything else after this is still situational in terms of tank items.
Sorry, but the only kind of Udyr I know that's worth having is the one who can stay in the fight the longest, interrupting everyone's ult and channeled stuff with the awesome BEAR RARAWRAWRAWR