'Excellent service, thank you!'
'Online experience was easy and great..wonderful choices and prices. I haven't heard from recipient yet. I wanted to thank you for reimbursing me for my purchasing mistake,thought it didn't go through the first time. will use you again'
'Thank you and your florist. It was exceptional service in every way possible. I was actually quite surprised that people should care so much as if my family was your family. Considering that my request was very last minute, I couldn't have asked for better service.'
You won't be able to dismiss this by usual means (escape or click button), but you can close it programatically based on user choices or actions.