I totally would give my (good) friends sex toys for Christmas. I think the main reasons not to would be

(1) they're squicked out by sex toys, or by the idea of me getting them one

(2) they're just not into sex right now, and it'd be pressuring them to get one. I wanted to get my sister something because she had her second and last kid recently, and I asked her and she was like "please, no! My spouse would be delighted, but I need a sex break!" So of course I backed off.

(3) Their spouse would find sext toys threatening. For my really good friends, I kind of don't care about (3) -- after all, if their spouses are threatened by sex toys, I'm doing them a favor because they need to get sex toys from someone else! But I know my friends' spouses, and they wouldn't Seriously Freak Out.

But, given that my friends are less sex-toy-ish than me, I'd probably stick with vibrators, and especially ones that are kind of high-end or have something special about them. Something like the MiMi.

I think that for heterosexual, female friends, the threatened-spouse thing is made worse by dildos since they're more like substitute penises -- and the larger and more realistic, the worse that problem is -- it kind of says "hey, sorry about your partner's penis." I think guys get that vibrators inherently have a different skill set than penises. The exception would be something like the Ella, which I think is pretty nonthreatening and has a different skill-set, too, because it's so specialized in its shape. About the Ella, my partner is like "thank God! Something to give my fingers a break!"

If I were giving a gift to a friend I knew was already a sex-toy connoisseur, I'd be a different ball o' wax: I'd be more creative about it.