This is something we`ve done a fair amount of. We believe that having a strong competitive intelligence read is key to success in your marketplace, especially something as crowded as online dating. I would recommend a few steps in constructing your competitive intelligence.
1) Find as many competitors as you can and spend some time on their sites. use search engines, industry reports, etc.
2) Organize a first cut into a spreadsheet
3) Create a set of screens to build a short-list of the best 10-20 competitors in your space
3) Define the "attributes" that you want to track for each competitor - things like business model, size/number of subscribers (use alexa, compete, quantcast), revenues (Dun & Bradstreet), differentiators, etc.
4) collect a full set competitive sites
5) Perform a SWOT analysis (Strengths, Weakness, Opportunity, Threats) on your market
6) create dimensions in your space that will allow you differentiate from the others... what market niches are available? (e.g. dating for military, urban dating, etc.)
7) create your messaging and strategy to target your new-found niche
8) Track your competitors through something like Rivalmap.com or Google Alerts
Hope that helps! Good luck!
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