A few minds...
PC Photo and Outdoor are real mags, as well as quite a few of the others offered in the course of the questionaire though some of the subscriptions are download only.
This particular questionaire is "Technology" driven even though the hook line is Photography. I've submitted identical questionaires for magzine offers of other interests and the question criteria and structure are identical. There are more than just Technology/IT related keys that'll further the questionaire and result in a free subscription but by far the more successful submissions are tech related; management and director related at that. The lion's share of market research revolves around the technology sector and marketing groups paying for magazine subscriptions and/or gift rewards is much more successful in data collection than cold call centers and bulk mailings.
Even if you complete the questions presented the subscription approval is still up to an separate approval process (based on your score as compared to the marketing data being mined) but ALL of the applications received are leveraged for a wide range of market analysis. This database is made available to entities whom pay for access to the data and or request specific market criteria.
I'm of two minds about the process. One, you DO have a good chance of receiving free material ('free' as in not putting a dollar value on your time to complete the answers). Two, your data IS used for their data mining even if you don't "qualify" for the reward advertised. (*Note, you might fit very well into criteria other entities are paying to harvest from the database but you won't be contacted for compensation from those interests). Alright, I'm of three minds about it; the third mind being that of media statistics reporting. Three, this is also one of the available 'credible' sources to media and news publications for reporting. Have you ever wondered where some of the statistics come from when a reporter/journalist/whomever states "of 10,000 people polled", or "the technology sector anticipates growth in...". Even considering that this type of 'research' data is culled and filtered for false positives, error correction and filler I don't know that I'm comfortable with it being the structure behind a not small amount of numbers presented to the public as 'news worthy' statistical analysis.
All right. That's all of my minds about it. That said, I look forward to receiving the PC Photo magazine and a downloadable Computer Gaming ezine. Ahh crap, that ezine requires a download. More bloatware...
Uh oh, another 'mind' just poked its ugly head. Last week I drafted an 'acceptable use' policy for corporate resources/computer equipment. Hmmm, my answering that questionaire and writing this dissertation suddenly has become not quite so 'free"
.
Looking forward to getting that Mag though! 
It is what it is...