OK. Long time reader but first time poster on this forum. I just couldn't resist throwing in my viewpoint on this one.
I agree with others that the calendar probably means something, after all the image always has in the past.
My view is that Apple is in need of a new product, a new category killer much like the iPod was originally for digital music. I know everyone thinks that will be the video iPod but I'm not so sure. I think the iPod with video will suit many people, especially with a few revisions to increase the battery life. I think there is a gap currently between laptops and PDAs and it's one of the reasons that the PDA market has stalled. PDA makers have continually tried to add new features to their products to satisfy the demand for change, however, in the process they have often lost the very qualities that made them successful in the first place - simplicity, robustness and instant access. The iPod could go the same way if they try adding too much more so I think it's getting time to stop adding. Meanwhile laptops have become smaller, lighter and more connected via wi-fi negating the need to have a PDA anymore. Many people have commented on tablet pc's. I use one at work and I would say that if you think of it as a computer it absolutely fails because the input mechanism, while OK for low input volumes, is way to slow for anything serious. Since most early adopters are techies it doesn't surprise me that they hated it, it is really more of a business tool, I use it as a window into the digital world while I am away from my desk, a kind of supercharged PDA. But in true Windows fashion it is too slow to boot up, and requires too many unnecessary actions to use it effectively.
So I think Apple will create a new type of digital tool which will be a tablet format and primary use a pen for input but be the size of a small notebook. However, just like the 5th Gen iPod was a music player with video capability I think this product will be a digital assistant with computing capability so you shouldn't expect to be able to write programs, or perform heavy video editing, or photoshop type work (although you will be able to because it will be running OSX), but it will be perfect for using iTunes in your living room or on the road, it'll have built in isight and bluetooth so you can use iChat or Skype whenever you are in a wi-fi enabled area (e.g. in an office it would be like a VOIP phone you could use in a meeting to contact someone). It will be about the size of an OQO Model 1 so it will fit in a pocket but not be as small as an iPod and therefore a perfect size to watch videos (yes it is the iPod Video as well). Obviously you will be able to use the address book and iCal as well as safari and other OSX apps, but it will complement a mac not replace it, as well as an iPod which will still be perfect if you want a smaller form factor and no input capability (remember all these devices will sync up so you just pick up the one that makes most sense given what you are doing)
This will create a new category of device inbetween a laptop and an iPod/PDA without cannabilizing either category (I think Apple knows we are all happy buy multiple complementing products from them). The device would continue to enhance the halo effect since it will be most effective when teamed up with a full blown mac.
Anyway, like everyone else I'm excited to hear what it actually is, but this is the device I am after and it would be both new and fun with a calendar connection, and consistent, if not an amalgam of a number of recent rumors.
Credit card at the ready Apple!!
