My version of VLC is from before Apple opened up the new APIs, so is Movist. Playing the exact same HD h264 file in VLC, Movist and Quicktime X player results in the same CPU usage of 37% - 41% on my 3 year old, 2.8 GHz iMac which does not even have hardware acceleration for h264. Playing the same file through Flash maxes out one of the CPUs at 100% and the video stutters and drops frames.

Flash's problem is not about hardware acceleration. If VLC and Movist can achieve the same low CPU usage as Quicktime X player on the same hardware means it's not an API availability problem; it's simply crappy, crappy code used in Flash.

The version of Flash before 10.1 contained PowerPC code still for intel processors!

Linux will never have a breakthrough on the desktop until it has a killer app that no other system has.

In the server room LAMP is linux's killer app. It's very effective and it is the reason for the majority of linux installs in the server room that I've come across.

Is there such an App for Linux desktop?

It's easy to say that, for most people, Linux would be more than enough. If you want to do email, browse the web and do basic things, then Linux is already excellent at that. But, for most people, the decision to which system to buy, most times, comes down to the unexpected needs that they may have in the future. That's why so far Windows is dominating. If you buy a windows machine, it's most likely to have any software that you MAY need. It's a safety net. Only Windows' extreme security issues have forced people to look at other system. Let me assure you, had windows been nearly as secure as Linux or OS X, people would have never, ever looked for other solutions.

When developers started moving away from the Mac in the 90s, the platform came very close to death. It barely held on to its measly market share because of cheaper Macs in the late 90s-early 2000s.

It wasn't until Apple managed to get Finalcut into great shape and its iLife suite and then OS X; those were things that people wanted/needed. The killer apps make people want/have to use a system.

I know of no such application for Linux on the Desktop.