Sorry Apple, screw iMessage if you're going to do that. It's extremely pathetic that neither Apple nor Google can make anything better than AOL's AIM. What a joke.
I'd gladly update to Mountain Lion if they didn't decide to screw a bunch of users over by removing Rosetta. Don't give me BS about how I don't need it because I DO NEED IT. Some of my apps use it. There aren't any updates to them or any new alternatives. The developer of one of them died in 2011. Also, there are a few minor things they removed in Lion / Mtn Lion for no good reason. It's still a better OS overall, but that one Rosetta problem just kills it.
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It's for the same reason facetime has to be bought for Snow Leopard. It uses some patents etc. that they are required to take payment for in a finished project.
You could argue that Apple should sell the Messages to Lion users, but it's simpler just having it as part of a paid OS.
They are simply not allowed to maintain the app for free. So either charge for it or include it in the new OS.
Yeah, that's not the way to gain iMessage users when every other messaging system out there is completely FREE. I really want iMessage to do well because it would kill SMS, which should die, but the way Apple's doing things, neither I nor anyone I know use it.
Giving out iMessage for free would put people in the Apple ecosystem and make them recognize Apple more. Google does this sort of thing constantly with its free, ad-free services.