As I have said before, I think the concept of strengths is overemphasized in positive psychology (read Overemphasizing strengths). I do, however believe in the usefulness of concepts like thriving and flourishing. While I fear that a primary focus on measuring, applying and developing strengths is too individualistic, focusing on thriving or flourishing allows for a more realistic interactive, dynamic and situationalist perspective.
In Barbara Fredrickson's book Positivity: Groundbreaking Research Reveals How to Embrace the Hidden Strength of Positive Emotions, Overcome Negativity, and Thrive (which, by the way, I am very impressed with), she explains the concept of flourishing like this:
"Like any other living thing, you too may either languish, barely holding on to life, or flourish, becoming ripe with possibility and remarkably resilient to hard times. People who flourish function at extraordinarily high levels -both psychologically and socially. They're not simply people who feel good. Flourishing goes beyond happiness, or satisfaction with life. True, people who flourish are happy. But that's not the half of it. Beyond feeling good, they're also doing good -adding value to the world. People who flourish are highly engaged with their families, work, and communities. They're driven by a sense of purpose: they know why they get up in the morning. Striving to flourish, then, is a noble goal. It's not just about making yourself happy. It's about doing something valuable with your day and with your life. Although flourishing is noble, it need not imply grand or grandiose actions. It simply requires transcending self-interest enough to share and celebrate goodness in others and in the natural world."
More about Barbara Fredrickson's work here:
Also read: Finding and using positive meaning