I don't think you have a reason to be worried (yet). I think this forum is great but it does create a biased impression about how fast cases are processed - because those who are processed faster are more likely to happily share their short processing times on the forum.
I applied for citizenship in mid-October 2006. I have a last name that is rare not only in the US but even in the country I came from. And it's not similar to any other names. I am US-educated, great job, American wife, a child, all the good stuff. Still I only received an invitation for an interview in June last month, i.e., 6 months (rather than 2 months) after the priority date. I think it's still pretty good. So - if you have a priority date in February - wait at least for August before getting worried.
Best,