I study the competition in my space. Because, as far as i'm concerned, they are the only ones that affect my sales. There is no point in me studying a large company - we are a small one which means different demographics, and marketing strategies.
I also use forums to check on trends, i've used webhosting.info to track competition, thewhir.com is helpful at times, sitepronews also tends to be interesting reading in the morning. I use all kinds of sources for my knowledge of the industry, however experience has taught me, there is no substitute for experience
As far as implementing certain strategies I read about - sure we'll do some test marketing, but I generally take such reading with a grain of salt. In other cases, i'll take parts of certain information and combine them into my own strategy. Webhosting isn't a standard industry. It's always being reinvented - so if you're basing your marketing strategy on a couple magazine articles, then you're already a step behind.
On the other hand, the internet is infinitely expandable, and thus, there will always be a market, and niches to settle into. When we began our establishment, it really seemed an impossible feat to gain any new clients - considering there were already thousands of providers out there....and yet, look at us now one year later. 1000 clients and growing - we started using marketing strategies from books, magazines, forums...and found that eventually you dry up the pool of clients available with that strategy....that is the day you need to get creative.
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