Dimmer noise

Point taken, but its the distribution of the heat in a useful manner, not the production of the heat, that I believe accounts for the difference.

I'll have to look at dimmers again and shop around. Getting the LV halogen dimmer was a special order at the time--couple years ago--and the price shocked me. It would be great if they were more broadly available.

Edesilva...For a recessed ceiling fixture in a one story house the heat distribution would be poor indeed. But for table lamps and the like which are used right next to people the distribution is good. I once (50 years ago) worked in an architectural office doing HVAC design, and I remember at the time being amazed by how much of the heat load on an AC system is due to lights.

I wouldn't doubt it. But, I still feel like for the overwhelming majority of the US population, going CFL is appropriately "green." (As a side note, I gather Home Despot is giving CFLs away this w/e for earth day.)

I would further note that ultimately anything I say here is probably hypocritical. While I haven't claimed to heat my house using light bulbs, I have tried to justify my vacuum tubes on that basis. ;)

Just today I had to deal with this very issue. I have an HT with dedicated circuits for audio, separate from lights. One of my 2" halogen can light bulbs burnt out. I went to look for a replacement and with no sales, they were $10@! No way was I going to spend $10/bulb long term to keep light in the room. (When I had bought initially, the bulbs were on super-sale and I didn't realize the long term cost)
I decided to switch the intensities of the can bulbs and the wall sconce bulbs. So, I got lower lumen can bulbs and seemingly innocuous 100w regular bulbs for the sconces.

They buzzed. The sconces had an audible buzz all round the room (after reading this thread I agree that it was filament vibration). I had to go to halogen bulbs in the sconces to get rid of it.
In my experience, lower watt bulbs (i.e. 40-60w) give less issues with hum in dimmer installs, and halogens have been golden. Halogens are much more expensive, but I've not heard them buzz.
I have a Lutron "Spacer" remote lighting system, which was not cheap, and halogens work perfectly.
Now for my rant:
As for the "green" bulbs, I feel they, in a word, suck. I spent plenty to buy dozens of them three years ago thinking I'd see big savings over the advertised "seven years" of life. Bought a bunch on "sale", which meant sending in rediculous amounts of rebates, just to get them down to a "reasonable" price of between $1-2/bulb. What a pile of B.S.! We (wife and I) have had several bulbs that need replacing annually! For a bulb that gives flat, deathly light and costs five to ten times more? Forget it.
We've concluded that the ripoff on these bulbs are the starting units. If the lights are left on continually they'll do fine, but if you have them on/of in cycles several times a day, forget it about long life. I figure I've spent a lot more and had more hassles with them than regular bulbs. I've started to buy regular bulbs again, because I'm sick and tired of the poor light, the cost and LACK of long life! It's a situation similar to the stripped down cars that were getting bogus EPA milage ratings, sometimes off by rediculous amounts.
And you want to see one of these "green" bulbs go black really quick? Put one in your garrage in the winter. Cuts their lifetime to about 8 months, AND when it's really cold they either produce only half the lumens or don't turn on at all! Can you tell I'm not thrilled with them?
I'd love to save the earth by using a light bulb, but at this point they've proven a rip off in my use.
If I had the common sense to try one or two, but NO, I had to buy dozens (because they're supposed to be so pefect, economical, long lasting, blah blah...)so that I'd have plenty for years. Stupid! Classic case of Caveat Emptor.

Man, I've been waiting years to say that! Felt good! Rarely do I rage about a product, but rarely have I been so disappointed in what's supposed to be a no brainer upgrade. YMMV

With the 11 lights in my home theater, I switched to super low watt bulbs. I did have buzz with higher watt bulbs. The bulbs I bought range anywhere to just 7 1/2, 15, and 25 watt.

Very low watts but its way better on a bulb, cause your not holding back sooo much wattage.

It is true, that the lower the watt bulb the less buzz to no buzz there is.