What I don't think OP realizes is two important points:
- computer hardware depreciates at an alarming rate (without bitcoins help)
- bitcoin is DESIGNED to depreciate hardware used on it (by virtue of difficulty)
So to this end, I think the future of mining is going to be in the favor of the casual home user who buys a GPU as a multi-tasker, to both play games and then mine for bitcoins while it's idle.
BUT
The exception here is that the OP is underestimating the general public's reasoning abilities. I use projects like Folding@home and SETI@home as examples. These projects are advertised to "use your computers spare cycles", without also admitting by virtue of your computer being on, it's costing you money. So every month, *@home users are donating $20-$30 to a project of their choice by proxy of their power bill.
AND THE KICKER here is that people do this for $0 in "in pocket" returns!
So as long as bitcoin can make someone $0.01 in pocket, people are going to mine. People won't necessarily INVEST in new hardware specifically to mine, but people will continue to mine.
So true!
![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif)
If you visit the BOINC stats sites and check the world top 100 crunchers and their rigs, these people have crunching farms. They spend hundreds to thousands of dollars a month without any $$ returns, all for the sake of becoming #1 and staying #1. Most crunch just for the stats, but their are lots who crunch because they believe that the project can help mankind in the present or future. I crunched for World Community Grid for 5 years due to their Cancer Research projects and only stopped because of the the monthly increases of the power cost this year (about $0.01 per kwh increase a month). Like last February the power cost was only $0.18/kwh, now its $0.26/kwh (geothermal power was supposed to be cheap
![Roll Eyes](https://bitcointalk.org/Smileys/default/rolleyes.gif)
. The power company even charge the cost of stolen electricity to all their consumers. Add to that cost of maintaining the rigs, just last month I lost 2 power supplies, 1 motherboard, and 1 UPS due to power outage/surges/fluctuations. Power surge strips didn't help. There's only one power company in our area so there's no choice but to accept their crappy service.