This "stunt," as you call it, did nothing to change that. In fact, it makes me have even less faith in Yahoo. How great do Yahoo's investors feel that their CEO is spending her time on trying to be designer instead of streamlining and turning her company around.
The one part of Yahoo's brand that was at least MILDLY interesting was its personality. I mean, the name is based on someone screaming! The new logo makes it look like they should change their name to "Ahem" or "::Clears Throat Politely::" Which brings me to my final point that, what scares me most about this logo redesign is that Mayer clearly doesn't understand her own company's brand perception. She had the opportunity to hone in on what makes Yahoo great and let that quirkiness shine, but instead she took a zamboni to her brand in a failed attempt to make a more "mature" look. If Mayer was so excited about literally tilting an exclamation point 9 degrees to the right as some sort of liberating self-expression, can you imagine how up-tight people must be over there now?