Aren’t guy veins always more prominent than girl veins? I had this association that it was a ‘manly’ type attribute somehow, probably from Red Cross nurses comments I think.
Right or wrong, I associate big visible veins with guys, so nope, not unattractive just masculine.
“You’re so vein, I bet you think this song is about you.”–Carly Simon 
Although some girls have somewhat prominent veins they are not in the same class as what will henceforth be known as “MAN VEINS!”. Take mine, for instance. If I use my left hand to choke my right bicep and pump my fist vigorously, my “MAN VEINS!” will pump up so big that you could move the ones in the crook of my elbow and on top of my hands by poking them. They slither under the skin like big green snakes. This is the part when people claim to profess disgust with my “MAN VEINS!” but strangely, the more swollen my veins get the more pride I have in the veins. Then I’m chasing my guests around the living room:
“Lookit this bastard! Ho-leeeeeeeeeee shit! Look! Look at it! I bet I could just about fit my pinky in there!”
“Oh wow! Look at this one! Touch it! It moves! C’mon, see if you can get it to go under that other big mother over there, who I’ve just named 'Victor McVeinenstein, Jr.”
…and then another cocktail party ends abruptly.
I like 'em, especially in the hands, because my dad has big “strong, manly veins”.
Unfortunately I have them myself, along with big man hands. I occasionally think they’re cool because they make me look strong and I like to feel strong. Unless I am wanting to feel pretty in which case I stop short at the hands.
I am like this also (from back in the day when I was a Registered TECHNOLOGIST 
) - “Ooh, nice veins.” I mean that sincerely.
Um, OP - oh yeah, big veins on guys is kinda hot, actually. And chasing people around the room with them would be very entertaining at MY kind of cocktail party.
Eh. shrugs
Eeeeew! Lemmee poke at ‘em-- poke poke. Actually my dad had them and called the ones on the back of his hands ‘ol’ turkey veins.’ They were fascinating, though I was eight, and find myself more neutral these days. The only veins I find a bit icky are the ones on ginormous over-developed steroid usin’ weight lifting addicts. Otherwise, how could you really object to what helps keep your average healthy guy alive?
Er, I hate to pop your MAN-bubble and admit this, but I can do this too. And I am most certainly not a man. And, I don’t generally like to draw that much attention to them at cocktail parties.
Really? I had no idea. Now that you mention it, I’ve never had a ‘vein comparing competition’ with any ladies, just dudes.
But it’s too late. I already royally decreed that they’ll be henceforth known as “MAN VEINS!”
I think big veins are kind of neat. I always want to poke them, but must refrain, because people generally don’t like that sort of thing.
I like when a man has good strong man-hands, and since man-hands usually have nice juicy veins, I like them just fine.
I can also respect them from a professional point of view, since I am one year (and a couple of certification exams) away from being a medical technologist myself. When you put the tourniquet on and the veins just leap out at you, it’s beautiful.
But the giant freaky Rambo arm or neck veins, that look like roundworms slithering just under the skin, are disgusting.
My dad has a big vein on the back of his hand, and when I was little it totally fascinated me to squish all the blood out of it, then watch it pop right back up.
As for myself, my veins don’t pop out at all (you can see them, though, because I’m really pale). Neither do my bones or tendons. Instead of having bony knuckles, I have dimples. I have the hands of a ten year old.
OK, this is going to sound weird, but I discovered a few years ago that I have veins on the soles of my feet. If I sit barefoot with my legs curled up on a chair, I can see this series of little green veins on the underside of the arches of my feet.
Mutant me!
:: assumes deep manly voice ::
I too am a technologist*, and I have prominent veins on my… hands.
[sub]*What’s the difference between a technologist and an engineer? According to my friend, who was describing someone who was doing pretty much what I do for a living, but was an engineer: about $30,000 a year. 
Among Canadian engineering people, anyways, a technologist is a graduate of a three-year engineering program at a community college. Technicians graduate from two-year programs at community colleges. Engineers graduate from four-year programs at universities.[/sub]
:: ponders return to gym, to enhance his veinliness ::
Yes, especially guitarists.
My husband (who is also a medical technologist) is really into veins. Or, at least he always notices them, especially mine.
It’s kinda weird. We could be walking along somewhere holding hands, and he’ll look at my arms or my hands and say something along the lines of ‘great veins!’
Ummmm, thanks?
I don’t care one way or the other, it’s not something I look for, and it’s not something that turns me off, either.
Ye Gods! There are all sorts of you “technologists” out there! And I bet you all have veins, too! How is it that I’ve never heard the word before?
Maybe we should change the titles of the technicians in my lab? I’m thinking something really cool sounding, like “techniquifyer” or something. They certainly deserve mad props.
mischievous
Yay!
I’ve always been extremely attracted to men with very little body fat. (Not bone skinny, you know, but with no layer of cushion between the skin and the muscles and veins and ribs and stuff.) So for me, visible veins = manly and sexy.
Glassy (not a technologist of any kind)
Way back when, when I was a technologist, it seems to me that we discussed how medical technologists are called technicians in the States, for some reason. Maybe the differentiation between technologists and technicians is a Canadian thing.