In my experience, there is a growing Android user base that would fit the 'Apple' category just nicely. Being: it should work and be a little fancy. Not users that would want to run Windows XP on their phone with Bochs or Ubuntu in dual boot
So regardless of the user-flavor, Bitcoin software should move towards usability and a good interface. From that perspective, the windows Bitcoin client is gruesome with long loading times, the blockchain seems not update-able unless you have 3 weeks to incremental update when a mere 100 days behind, and your HDD seems to die in the process (at least, it sounds as if it is dying).
What a difference with the simple BitcoinSpinner app for Android. Simple, fast and more or less 'instant payment' (if payment is made, the system announces a payment coming in). That's the way an average user would want to work with Bitcoin (and so do I). Of course, the main difference from the official client is that the Android app relies (as I understand) on a server to get blockchain information.
Nevertheless, mobile appz are showing the way forward.
*Instant payment (most payments will probably not be tampered with)
*Virtually no fees
*Nobody can stop you
Add the properties very interesting for the second/third world
*No bank account needed
*Again, virtually no fees
And for the people that frown upon fiat and central control
*Limited supply/store of value/no fraud
*Free from interference by government/monopoly
Depending on the user's interest in technique and society, you would have to focus on these aspects of Bitcoin.