It is wonderful stuff. I doesn't necessarily taste any different; rather it has a much thicker and richer texture. It is almost like what regular yogurt is like after you strain it through cheesecloth overnight.
These days, we have a cup of 0% Greek Yogurt most mornings, with homemade granola. An excellent, healthy breakfast. It is a great substitute for sour cream in too-hot chili (actually, it is better than sour cream for that). It is also a remarkably good substitute for cream cheese. (That substitution works well only on open-faced applications, such as on crackers, or on one-half of a bagel. It isn't as rigid as cream cheese, so under the pressure of being between two halves of a bagle, the yogurt will slip out. However, in an open-faced application, I contend that the Greek Yogurt does what you want cream cheese to do better than cream cheese, and it is a lot healthier.)
The Chobani is a good bit better than the others, though we've used Oikos and liked it.