These are the guys that were developing and using tracking scripts ( before Analytics and Woopra ), CMS scripts ( before WordPress and Drupal ), spy tools ( before SpyFu and MixRank ), and split testing scripts ( before Optimizely and Visual Website Optimizer ) that we now take granted in our careers. The developments in these areas were all driven by money and ROI, and became the default tools and mindset of budding online marketers.
Focus on reviewing products that fall within your niche. Then, leveraging the rapport you have created with your audience and your stance as an expert, tell your readers why they would benefit from purchasing the product you are promoting. It is especially effective to compare this product to others in the same category. Most importantly, make sure you are generating detailed, articulate content to improve conversions.