I was wondering... If you change from a werewolf to a vampire, do you lose the perks that youve gained for the werewolf say, if you ever were to change your mind and decide you dont want to be a vampire? and vise versa.

Unless my memory is skewed, once you cure your lycanthropy, you can never again become a werewolf, so the question is moot.

As I don't have the DLC yet (PC user), I have no idea if VL works the same way, but the nature of the transformation would lead me to believe that it does.

They give you a second chance to become a werewolf if you cured it after completing the quest for it...

Also there are now wild werewolf encounters, don't know if they can pass it or not...

But to the OP....I'm not sure yet.

I ran into a werewolf on my way to the vampire keep (the name escapes me). It was a hunter fighting three horkers. I decided to help... then he transformed and now.... now I have a new loin cloth. LOL. But yeah they are there.. something was weird about it though. It still had armor on and was attacking with a one handed weapon. Maybe it's a work in progress.. maybe i was really tired or maybe it was just a random glitch. Go hang around some hunters at night. You might see what I mean. . And thanks for answering guys. I might just have to find out on my own.

Apparently they can't, since those werewolves are the traditional disease versions, where as the one that the Dragonborn can obtain from is a blood ritual and a blessing from Hircine.

You dont lose your perks. So if you decide to become a vampire and your a werewolf those perks are saved in case you ever want to return to being a werewolf.