Media coverage is not always favorable and when it is, it deserves recognition. You will strengthen your business relationship with this customer by reinforcing the public accolades.
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<Recipient Address Goes Here>
I just <what you saw or heard>. It was an excellent piece and I'm sure it will generate a lot of interest.
<What you noticed or liked.>
It is gratifying to see <a company/someone> get positive press coverage these days. Congratulations.
encl: <List of enclosed items goes here>