Where do individual users and corporate spend their IT buck ? From my experiences the following are functional areas where people invest in IT.
1. Personal productivity (letters, documents, spreadsheets etc)
2. Accounting (tally etc)
3. Liesure (DVD rippers et al)
2. Transaction processing.
The rest of the market is blurred and does not bunch up. The key here is that if one were to assign an arbitrary weightage to each function and calculate the cost per function as a ratio of the speed of the processor and memory installed, the optimum point was reached maybe 5 years back. The cost of running tally on modern hardware (P4) vs older hardware (p2) is higher per transaction. Which begs the question as to when some one will create a purpose built system (using say VIA or transmits) that runs off a broadband connection and runs say 3 applications.