Can anyone think of a case in recent memory where the fear mongering over a proprietary, wisely used, web format lived up to the doom & gloom predictions? Seems

Can anyone think of a case in recent memory where the fear mongering over a proprietary, wisely used, web format lived up to the doom & gloom predictions? Seems like it usually turns out fine in the end or, over time, a more open solution wins out on technical merits and better/cheaper accessibility of encoders. In 2010 I still see animated GIFS on a fairly regular basis, MP3s, even RealMedia which thankfully VLC plays well. I don't think it's a bad thing Mozilla is trying to make a point here about open formats but they shouldn't take it too far or they risk really hurting the web by committing market share suicide and limiting the diversity of commonly used browsers.