I'm 20 and still a virgin (in basically everything). I've written quite the rant below, so be forewarned. It's long, messy, and might have gotten a little preachy.

I have a few thoughts on the idea of virginity, not the least because I come from a conservative cultural background and took a vow not to loose it until marriage/equivalent. I consider virginity to be not having intercourse: not having genital contact with another person. "losing" it happens the first time you have sex, which I define as genital 'contact' with someone else (For clarification: intermediaries, like a double ended dildo or a dildo for pegging, count as 'contact' even if there's no'skin to skin' contact). I say 'another person' because you need two or more people for it to count as sex. A single person masturbates, even if there are toys involved. As much as you love that particular vibrator or toy, the last time you used it, you weren't shagging it.
I don't think that (for a female-bodied person), 'loosing your hymen' means a loss of virginity, because the whole idea is dependent on the idea of penis-in-vagina sex, and ignoring (for the moment) what that implies about couples that aren't M/F, it implies, essentially, that the hymen is some kind of "safety seal" of purity, so that any children from the woman should be more likely to come from her male partner, and likely her husband (this all, by the way, is the standard view for many conservative schools of thought, often religious, but not always). Fuck. That. This whole view completely objectifies women, and I find it a ridiculous, out of date concept. Furthermore, it doesn't even make much anatomical sense. The hymen is a membrane stretched over or just inside the opening of the vagina, and you never fully "lose it", unless it's been surgically removed, or if a large object (like a baby) passes through it. Even then, there may still be remnants of it. It's often shaped like a crescent (other shapes exist, but are more rare), and it can be stretched or torn by any number of activities, from exercise, tampons, fingers, or intercourse. Personally,I "lost" or tore my hymen due to a tampon, but I've never had sex. But I didn't lose my virginity to a tampon.
For the guy involved in this M/F example, virginity might just be counted as when he first had sex, most likely also penetrative. That's also a problematic view virginity because it's limited by the terms of the situation. It doesn't account for the chance (and likelihood) that the genders of those people who aren't in a straight relationship. Two (cis)women who are together could arguable both be virgins because neither has the genitals to penetrate the other. If someone is trans or gender-fluid or any number of identities or orientations, that shouldn't make a difference as to how we define virginity.
As to whether or not it's a big deal... I think that it depends completely on the individual involved. Not their parents, not their society or culture or religion, etc.;though they can take into account what ever factors they may want consider, in the end, it depends on you. It's your body, your choice. If you want to save it until marriage for reasons x,Y, and Z, go right ahead. If you want to lose it tomorrow to your significant other/that person you just met whose into you/etc. go for it, as long as you choose to do that (and who ever else is involved consents too). If you end up never losing it, that's fine too.