We were just there on March 10. Garden Grill is our favorite character meal, and our arrival night tradition. Based on another outstanding experience there, the tradition will continue!
The food was still good (although I'll admit it's not the best at WDW, and I'm not a fan of the new blueberry buckle dessert.) The character interaction is still great - actually even better this last time!! Our youngest jumped up and down when he saw Mickey, and Mickey jumped with him. Our oldest forgot his autograph book in his brother's stroller and Chip promised to return to our table - he did. We usually see each character twice during our meal, anyway, but it looked like Chip made a special trip. This is the least rushed character interaction we've seen at Disney - it's more than just autographs and photos - they spend additional time with the kids and I never felt like they were rushing away.
The lower level booths are great for our family - we seat our three boys at the ends of the booth. It's a relatively relaxed atmosphere for meeting the characters, and the boys love how the restaurant rotates so that you see different scenes from the Land ride during dinner.
So we highly recommend Garden Grill! Have fun!