I was just checking out the new Snow Leopard page [via TUAW] and it is quite defunct of anything remotely interesting. Sure, Exchange integration is great, but it only supports Exchange 2007. That's because Exchange 2007 supports standard web services (something that Microsoft should be applauded for doing). Now, I'm no OS X developer, but I suspect that incorporating, say, Exchange syncing of Address Book contacts is no more complex that adding the GMail Address Book sync included in the 10.5.3 update. Why a whole OS for this?
And why would I would I care in one year's time about an OS with a smaller hard drive footprint? I can buy a 1TB drive for around $200 these days. I have unlimited online backup via Mozy for $5 per month. I'm not sure how big Leopard is, but let's say its 10 GB. As a percentage of my primary hard drive, remote Airport disk and Mozy backup, that probably represents about 0.1% of my hard drive space. So if Apple manages to reduce the OS size to 1/10 of its current size, that will save me a staggering 0.09% percent of storage space.
And that's "in about a year" when hopefully laptop drives will be approaching 750GB, online storage will be as close to free as possible, and you'd just carry around your iPhone instead of your laptop for most media viewing activities.
So call me cynical, but I can't why anyone should get excited about a Snow Leopard or why I would consider paying for it.
