Funny, i happen to know my sampling techniques and statistics quite well as they are a major part of my job which i am good at and Vis did not handpick the posters that replied or influence them in any way. Hence the sample is random, and i don't know the sample size but i am pretty sure it is large enough to represent the opinions equally. The people who replied were not hand picked so you wont find a sample more random than that, with posters of all ages and opinions replying.
Stan might think you're good, but I'm not all that impressed. I see you stated the sample wasn't random without any reasoning or explanation as to why you would think it isn't random. If you are gonna suggest the sample isn't representative, i am afraid i am going to need more reasoning than just that.
No problem, I actually did on another thread where I brought this up with Vish but you're quite right I didn't do it on this one. Whilst I wouldn't doubt your proficiency at your job, the sample is not random as it is most evidently not an unbiased sample that has been taken. For it to be a random sample of the 'posters on this forum' each poster would need the same probability of being represented. This poll does not exhibit such a chance selection of participants. Even if we are happy to narrow down the cross section of posters to those who happened to be on the site on the day at which that thread made it onto the most recently commented list (already making it unrepresentative of the general posting population though we are still within the realms of reason here), it is still a biassed sample as you are only taking those posters who saw the poll on that day, and would choose to actively engage. Now as with all 'surveys' you run into these problems of bias so you could discuss the extent of how representative or unrepresentative it is (though as demonstrated it isn't really representative of the posters as a whole already), but this is most certainly by definition not a random sampling technique.
If the first year analysts at my company make this mistake its strike 1 for them as its a pretty common misconception on what random sampling actually is. Apologies for not backing that statement up with reasoning, I got lazy as I explained it on another thread or two.