I like your first point, but your second point makes no sense. Products are not currency, and talking about inflation/deflation in products does not make sense, unless people buy them as a long-term value-store in which case "assets" might be more appropriate. Except they're still not fungible so they can appreciate or depreciate, but that's not inflation or deflation.

To explain: The fear that often is associated with deflationary currency (like bitcoin) is that no one will spend it, because waiting always gets you a slightly better deal. And if that happens the economy will grind to a halt with everyone waiting to spend. The point of my second statement is that we have examples of cases where even though every month your money buys more, people still do buy things.

There may be specific examples (HDTV) where waiting means your money buys more, but overall the more you wait the less your money is worth in the economy due to inflation. Technology making products cheaper is not an example of deflation. Inflation and deflation pertain only to currency not products.

If however you hold your currency and everyday its worth more, besides the bare essentials there is barely an incentive to spend it. Also there is no guarantee that the HDTV will become cheaper, however it is guaranteed that a deflationary currency will gain value the more you hold on to it.

    Inflation and deflation pertain only to currency not products.

Inflation is when your currency buys you less stuff tomorrow than today. Deflation is when it buys you more. Falling prices due to efficiency gains caused some deflation during the industrial revolution, and technology making products cheaper is definitely a kind of deflation. From Wikipedia:

    Growth deflation: an enduring decrease in the real cost of
    goods and services as the result of technological progress,
    accompanied by competitive price cuts, resulting in an
    increase in aggregate demand.  A structural deflation existed
    from 1870s until the cycle upswing that started in 1895. The
    deflation was caused by the decrease in the production and
    distribution costs of goods. It resulted in competitive price
    cuts when markets were oversupplied. The mild inflation after
    1895 was attributed to the increase in gold supply that had
    been occurring for decades.

Ah I see, that makes more sense. Yes, I think fears of deflationary currency are probably quite a bit less rational than fears of environmental cataclysm as long as society doesn't come to term with the fact that there are in fact physical limits to growth on some time scale.

That's a pretty irrational fear... If my money grows all the time, why wouldn't I buy stuff? I'm buying most of my Humble Bundles with Bitcoin and it's great - every time you pay less and less and by the time the next Humble Bundle is available my money has recovered itself to more than what I had before... I may have had doubts to buy some of them with another currency, but with Bitcoin it's just a no-brainer. You'll get it all back and more.

You don't buy things in HDTVs so that doesn't really matter.

In the frame of a single transaction, and the point I'm making, it doesn't matter which side of the purchase equation causes the deflationary more-for-your money effect.

The point is that the more-for-your-money effect does not stop even discretionary purchases like TV's from happening.

It slows some things like computer purchases. Puts a lag on a variety of things.

Also, why bother to invest money if you can just sit on the cash and benefit from everyone else's economic activity?

Deflation bad.