This may or may not be related, but I've had issues in the past using Google Fonts, particular in Google Chrome:
Font Used: 'Share'
Problem: In a header (h1) long enough to wrap, Chrome would render the font correctly for the first line and every other line after, while the lines in between would fall back to the next font in the stack (in this case, simply 'sans-serif')
Solution: I had been using Twitter Bootstrap for this particular build when the issue occurred. Baked into Bootstrap 2.3.0 (in others, I'm sure too) is a header rule for text rendering: 'text-rendering: optimizelegibility;' -- changing this rule to 'text-rendering: auto;' resolved the problem for me.
Read more here: https://developer.mozilla.org/en-US/docs/Web/CSS/text-rendering