It has been a big year in personal technology, from the debut and early success of Apple's iPad, to the rise and continuous improvement of Google's Android smart phone platform, to the continued surge in social services led by Facebook and Twitter.

So I thought I'd take a look at the challenges and opportunities facing some major players in consumer tech in 2011. As with all my columns, this one is focused only on products and services provided directly to consumers, rather than to businesses. Also, as usual, this column isn't...