OS X 10.6 (Snow Leopard) was released on August 28, 2009. Version 10.6.4 came out last in June of 2010; it’s now a good upgrade for a 10.5 machine. It took Apple about 10 months to beat the OS into decent shape, which is a bit of a problem if you’re considering a new desktop machine. Unless you enjoy computer hassles, you should buy new Macs a few months before, or six months after, a major OS X update.
Apple’s iOS environments are much simpler than OS X , and Apple has many fewer “system apps” to test  – so it’s not surprising that their iOS updates have been more reliable than their OS X updates. The first couple of iOS upgrades went pretty well. Things are getting more complicated though , and now we’re seeing real problems …
… In a strange twist with what appears to be a security issue, users of Google Apps who set up their accounts using the Microsoft Exchange settings (aka ActiveSync) may find that their iPhones have been set to auto-lock in one minute…
…. While we can't help much with the activation errors that some of you have had (potentially due to overloaded communications between Apple), we can help with the infamous error 3002 that many iPhone 3G owners are seeing when attempting to update their device…
Both of these bugs would have been a waste of time and energy for us. It’s summer in Minnesota, I have better ways to spend my sunny days.
These bugs will get sorted out through a combination of third party, iOS and iTunes updates over the next month or so. If you only have older phones, the smart move is to wait until August to upgrade. If you’re buying a new phone, however, you have to use the new OS .
Which is why you should buy a new iPhone or iPad in September. Apple seems to have very consistent phone release cycles (though not all will be major updates), so if you get a new phone and a new 2 year contract in September you’ll be in phase with the release cycle. iOS device prices tend to be stable over their life cycle, so a purchase in September gets you the best life cycle value with the least upgrade troubles.
In my own case my 3G is painfully slow  so I’ll probably buy in August, but I’ll aim for September for our next upgrade cycle.
 I’d like Apple to get the heck out of the apps business altogether due the very long bugfix and upgrade cycles of systems apps, but that’s another post.
 The complexity is increasing very quickly with the iPad and with iTunes OS X and Windows XP/Vista/7 dependencies. There are also some iPod dependencies due to a shared DRM infrastructure. For example, iTunes 9.2 sounds like bad news for older iPods. I’m waiting for 9.2.1. Since iOS4 may require iTunes 9.2 that’s another reason to delay iOS updating.
 At least for that device, you don’t have to update all devices you sync to the same iTunes account
 Apps are being developed for modern devices, so upgrades expect more RAM and more CPU – especially the former. I also sync way too many calendars, contacts sources, etc for this device – I’m basically flogging it.
July 17, 2010: Wow, I sure called it for 2010. This year it's probably a good idea to wait until November and see if Apple is going to come up with fixes for the proximity sensor and antenna design flaws, not to mention the worse than 3GS connectivity.