Hey! I am still on a long trip so please excuse any errors in this post, I'm just trying to give my 'quick' 2cents.
Assuming that you are trying to get a specific driver working
It is usually easiest to find an example of someone who already has that driver working and then go with that. Obviously I am a big fan of M2 and I have been hoping that other people will try it out, but it is the least verified of the 3 methods and therefore the least help is available for it. If you just want to get it done, I suggest M1.
My answers to your questions:
Q1 & Q2.
This summary seems correct, however Pure Krome's method evolved significantly into XP Basic CD Unattended SATA/RAID Install , How to avoid hitting F6 for CD Install.
This is effectively M2 to the 20th power which is to say that it is somewhat complex (in my opinion anyway). However this is not to say it is incorrect, and may work for some drivers that the standard M2 method does not work for. As for my credit for M2, I certainly did not 'create it' however I did write the most recent and (hopefully) most complete guide. This newer Pure Krome link is more appropriate for something like M2.b and should be used instead of the other Pure Krome link. For those concerned that M1&M3 involve too much direct hacking of driver setup files, or have drivers like the 3ware's with more than 1 driver per Hardware ID, M2 may be the best alternative.
You may also want to reference the M1-style integration of certain drivers into GM's XPCREATE, which is very easy for people who have those drivers. It's only a subset of the drivers that have been shown to work with M1 however.
I would try to include only the most current/complete topics for each method since there is a lot of old/incorrect information that has been talked about while people were simply trying to figure things out
. Actually your current list seems very good.
I have no personal experince with Pyron's method so I can't say much about it. I like the M1, M2 etc. nomencalture so M3 gets my vote, but I will leave it to someone more 'senior' than me to confirm this naming.
M2 does NOT require editing of TXTSETUP.SIF (well M2.a? anyway, I have not looked at M2.b in some time so it may or may not).
I have no experience with this either, however Bâshrat's is usually right on top of things and you should get an answer from him pretty soon I would think
I think that Bilou_Gateux is showing these 2 tools as proof that the M2 method is the 'proper' way to install drivers (since these large companies appear to use it). I personally feel that the 'proper' way to install drivers would be for Microsoft to let us drop the driver files in a folder and let-er-rip without any setup file hacking. I don't think this will happen any time soon. I am willing to bet that there is a whole lot of 'other' stuff giong on in these 2 tools that makes the M2 method work so well for them, I mean c'mon they want you to buy a service contract to use them.
Okay, I will end by saying that if you anyone has a chance or inclination to try out M2 for your hardware please do so! Right now the only confirmed M2 drivers (that I know of) are the 3ware 7k/8k drivers.
Edit: Yes! I am aware that I need to work on my conciseness