I'm sure that it's not great to have around. Personally, I try and do everything I can to minimize my chemical inputs, (gas, fert pesticides etc...). I just see my property as a leisure property, and I want it to be as natural as I can have it. I live in the city, and I'm surrounded by gorgeous lawns that get sprayed in who-knows-what every month... I use my property to escape all that. I like to see it imperfect! I have no problem using it for hack and squirt, but (it's kind of silly) I just hate spraying my plots. In my opinion, it's a somewhat necessary evil, but often times it is overused. This is why people think GMO's in and of themselves are bad! The GMO's are fine, but the cultural practices that are often times associated with them can be a problem.
All that being said, I am not very worried about gly itself, but I am worried about the surfactants and other non-active ingredients. I'm also not as worried about the acute side effects of being exposed to it, but rather the long term chronic effects that we get over a lifetime of exposure. It will be very interesting to see if there are any major health changes in people my age and a bit older that have been exposed to it their entire life, and more importantly during their developmental years. Unfortunately, as with most large commercial chemicals, it will take something along the lines of the DDT catastrophe to make people reconsider. This isn't just a gly problem, but a chemical problem in general. Any time we synthesize something very similar to a naturally occurring compound (e.g. neonicotinoids) there is a very large possibility of them having unintended consequences. It's just a fact of the world that we live in.
Similar to Natty, I'll be trying to establish a gly-free planting this summer. I WILL be using gly to get a clean seed bed. But after that I'm trying to use crop rotations through the summer, and fall, and then frost seed native prairie and a perrenial mix. It's not for everyone, but I think it'd be pretty cool to get it to work!