+1 for barney
Security. Reliability. Availability. Well put.
We're not there yet, and never will be. Well, at some point, but we're nowhere near right now. However, for casual software, I think we're there. For non-casual software...
Starting at the last there - Availability. This will always be a problem in remote areas. Satellite is the leveler here at the moment. Many parts of the world have serious issues here. Even electricity is a problem in many places. Even in some big cities. (My wife told me that they had another power outage in Ho Chi Minh the other day. Very common.) An onsite generator solves this. Again though, you're back out of the cloud.
Reliability. This is actually pretty good, but for many applications this will never be satisfied in the cloud. e.g. Mission critical applications, hospitals, etc. You can't have outages when lives are on the line. C4 systems are at the cutting edge here.
Security. It will never happen. Not because 2048 bits isn't enough, but because governments will not allow it. If they can grab your private parts, what makes anyone think they won't grab your data or spy on you? (And yes. THEY ARE out to get you~!
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It really all depends on the application itself. For casual software, I think the web is the way to go. There are no more barriers anymore.
To be blunt, those that don't have it available to them don't matter because they don't have any money, and that's all that people care about (collectively). (If we actually cared (collectively), we wouldn't allow the 16,000 kids that died of diarrhea today to die like that. That they died shows that we really don't care.)
For those that don't have reliable access, again, they just need to deal with it for casual usage.
For security, too many people don't care and are willing to sacrifice here. And for most casual software, security isn't really all that important. Really. Oh, so your game got hacked and you lost your 35th level whatever. Boo hoo. It's not really all that important. Banking on the other hand is totally different.
Blah... I have to go pack! I'm just procrastinating now.