Going forward, attracting customers to replace mobile phones is key, and requires more capable and feature-rich phones. This will accelerate the trend towards smartphones, which have the capacity to offer users more and more of the Internet and media experiences that PCs are currently used for.
Smartphones which can utilize the display of TVs and other devices, may further supplant some of the usage (or need) for PCs. Also as consumers familiarize with the UI and environments of smartphones, the door is opened for the migration of smartphone environments to larger devices, for example netbooks. Google's Android is poised to be a strong contender in this latter trend, already having a basic x86 netbook port and picking up many new power-hitter members in it's Open Handset Alliance. Note that some of these players manufacture PCs.
Look for a transition from the shrink wrapped software model to the online app-store model, exemplified by the iPhone app store or Android market. A smartphone alone, or a smartphone plus netbook will become more the focus of our computer lifestyles. Some new consumers will enter the trend, never buying a PC in the conventional sense.
While 3G and more advanced data services help smartphones gain traction as tomorrow's computing device, WiFi has enabled smartphones to be a first class computing citizen. WiFi usage from smartphones has increased sharply and will continue to do so. Look for WiFi support on lots of electronic devices.
The transition from handset to smartphone is obvious, but how many of the related vendors are paying attention to the smartphone to smartbook transition and relationship? I believe answering that will be an indicator of who floats to the top.
Disclosure: no positions