Uh-oh, is that a dark cloud on the horizon? Macworld Expo is generally a happy, carefree time full of music and love and dancing in the mud and not taking the brown acid and... wait, that might be something else. But in any case, Expo is generally the feel-good hit of the summer for Mac users who can make it out to the show, and this time around it promises to be an even bigger love-in than usual: this time, as you're all well aware, marks Mac OS X's "coming out party." Sure, the lickable OS may have shipped over three months ago, but the real shift will happen when every Mac ships with Mac OS X installed as the default operating system. When Steve said that would happen "this summer," everybody assumed he meant at the Expo.

That dark cloud threatening to rain on our Happy Time, though, is that the version of Mac OS X that ships at this long-awaited celebration may not be the version we've all been waiting for. It's no secret that Mac OS X 10.0 was meant for "early adopters"-- also known as "people who can overlook slothlike performance, a zillion missing features, and a stunning lack of available applications just as long as the buttons are blue and throbbing." (in other words, people like us.) All versions of Mac OS X released publicly to date are collectively referred to as the "Cheetah" release; "Puma," or Mac OS X 10.1, is supposed to offer dramatic speed improvements and several missing features-- it's the version that the average shmoe can use and enjoy. In other words, Puma is Mac OS X for the rest of us. What could be more logical than new iMacs running Puma being released at Macworld Expo, Mac OS X's coming out party?

Sadly, logic doesn't dictate software development schedules-- or their slippage. As faithful viewer Kerry B. points out, Think Secret reports that several sources now claim that Puma won't be ready in time for the big shindig two weeks from now. Instead, Steve may "demo 10.1 onstage at Macworld, but the public release will come after that," possibly as late as September; as a result, any new Macs that Steve unveils at the show "will ship with 10.0.4." That scenario makes us slightly nervous; we've been using 10.0.4 since it became available, and while it's better than 10.0 was, it's still not the version of Mac OS X we'd like the world at large to judge. The last thing Apple needs on top of the megahertz myth is for reviewers to tell the world that the new Mac OS X iMacs "feel slow."

For what it's worth, in his latest report, the Naked Mole Rat generally concurs with Think Secret's take on the sitch, at least on the lateness tip-- he reports that Puma is "now due to ship a few weeks after the Expo"; however, he also claims that the new Power Macs that Steve will likely trot out onstage probably won't ship until Puma is preloaded. Whether this "hold the hardware for Puma" tactic would apply to new iMacs as well remains to be seen. Personally, if it were up to us, we'd probably opt to wait until Puma was done before chucking Mac OS X at the world at large. But while it's true that Apple only stated that Mac OS X would be ready for prime time "this summer," and even early September still officially qualifies, it'll be a shame if Apple misses its chance to ship Puma at the Expo loaded on its new hardware. Hey, this is all just rumor, and maybe Puma will be ready for the show after all-- but if you're headed to the Expo, you may want to pack an umbrella just in case, because that cloud's looking a little angry to us.