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They have been discussed, check sites such as www.rfidprivacy.org/blog/archives/000090.html .

Well. He has spoken out against software patents and he feels strongly about RFID.

There are at least two blogs on RFID and privacy, at: www.rfidprivacy.org and www.stapleton-gray.com/surpriv/

First, thanks for the reply. I wasn't sure you'd write back.

"If there are individual readers for each one, build a device that incorporates all of them try one at a time until you get an expected result." Sorry, it doesn't work like that. You can't just tape them all together. See, the problem is that they're all emitting and reading RF, and if you have more than one active at a time, you'll get nasty interference. The fact is, it is hard to build a device that does multiple frequencies and protocols.
I really meant, run one reader on one frequency - then if you get no good response, turn its transmitter off. Then try the next one and so on, in other words avoid interference by trying one at a time. (But again.. I'm no RF engineer, this is just how I imagined it and am just clarifying what I ment)

"But what makes you think anti-collision is even necessary for my argument?" Anti-collision is necessary for any reader on any of the of the protocols you mentioned. Otherwise if you have two tags in the field and your reader tries to read the tags in the field, they'll both try to answer at the same time and interfere with eachother (collide). AC is one of the hard parts of any shared medium communication, be it aloha-net, ethernet or RFID.
While anti-collision may be required by those protocols, many uses of RFID tags (as I imagine them) do not need to deal with this. A "key" reader for example - if there are two tags in the reading range, it shouldn't unlock the door. Only if there is one key, and it has a valid authorized code should the door be unlocked. Same goes for Speed Passes and many similar applications. In these situations it would almost be a "feature" that they don't work when there are two keys present. Of course anti-collision mechanisms will definitely be needed in, say a retail environment, or with long range tags.

Anyhow, you don't have to be an RF engineer to participate in RFID discussions. But if you're completely misinformed about the subject, then you're just spreading FUD, and that's what I object to.
You're absolutely right, and I stand corrected on several issues you've pointed out.

"They don't have batteries, which is the only reason for their limited range. They get power directly from the radio waves." Half-true. Some RFID tags are powered or active, some are unpowered or passive.
I actually didn't know this when I wrote this, I only found out when I did some more research today. For me, when thinking of RFID tags I just didn't think of a powered device which to me seems more like an integrated wireless device. Again, I stand corrected.

"They are now weaving them into of clothing, they are inside your tires, and in the handle of your razor." They are not weaving them into clothing. I challenge you to find me one quote where they say they're doing that. I think that rumour may have started when a Wired article claimed that "Prada already embeds RFID inventory tags into its clothing". But a little research shows that is simply a tag that they put on in one particular store, which is probably removed when it is sold, and it is very visible to the customer: "Pick up any pair of shoes or handbag or dress and you'll find a clear RFID tag, with the antenna and chip clearly visible." See, it's the antenna that's difficult. Sure, the RFID chip is tiny, but the antennas are pretty big, normally on the order of 10cm by 3cm or so, so weaving it into clothing just wouldn't work.
Here are three examples: Benetton, Marks & Spencer, and KSW-Microtec - they make wearable/washable tags specifically to be embedded in clothing. (These may not be the best links, but further reasearch on each of them can easily be found by googling.)

As for tires and rasors, I sincerely doubt that that's the case

I wonder if someone is goign to make a killing by selling little RFID chip & reader detectors. Richard Stallman suggested RFID detectors and destroyers as a challenge for privacy adocates. Perhaps clothing with conductive/dissapative threads will be the next fashion trend (just don't count on your cellphone ringing if its inside your pocket ;) ).