(Software doesn't count, because it is easily available to everyone through 30-day trials, including to reviewers.)
Oracle tried to get Google into trouble by revealing the search company was paying bloggers to report unfavorably on the database company and its law suit against Google. Google said Oracle was doing the same. The judge was concerned the paid-for writing may have negatively affected the court case, and asked for lists of names of compensated bloggers. (Today the judge said he would "take no further action regarding the subject of payments by the litigants to commentators and journalists.")
A similar situation occurred some years ago when Autodesk sued Solidworks over orange rectangles in its marketing that were colored orange and were made of rectangles. Solidworks sponsored (the polite term for paid) a CAD journalist to sit in the courtroom and report. It was a useful service for all, but the one thing the journalist didn't report was his financial arrangement; th news came out later.
Blogger Matt Lombard at one time insisted that bloggers like me are tainted for taking money from ads. His blog now runs ads. When advertising comes from a variety of sources (not just one vendor all the time), then there isn't the concern, especially when ads come from ad servers whose content over which the blogger has no control, like Google AdSense; in my case, I use the Opera browser's Block feature so that I can't see which ads run on this blog.
So, some bloggers still do their work for free; others sometimes get compensated through ads, free hardware, and travel refunds; and the rest are known employees of CAD vendors.
With many of us bloggers being open about sources of conflict income, it is democratic of CAD vendors to balance the scale by reporting their compensation to non-employee bloggers and magazine writers.