I received my first official patent certificate last week, and was invited to comment here on my perspective on patents. However, my opinion isn't something I felt could be compressed into a simple comment, so I wrote it up on my blog:
However,for those who aren't interested in reading the article: software patents are generally not a good thing, but are required to operate in the current IP climate, particularly if you have investors who always want you to protect your operating space. As long as patents can be used "offensively" by your competition, you have no choice but to collect your own set to use defensively.
As for the merit of patents: A patent is a monopoly which is granted to someone to help them recoup their investment in a particular technology and an incentive for the inventor to disclose it. (ie. incentive to not go the trade secret route.) However, I feel that patents are only worth granting if the initial invention itself was the product of significant investment or hard work. (eg, getting FDA approval for a drug can cost billions of dollars.) When patents are given out for trivial things (eg. a new way to shop online), then you're providing a monopoly to someone for disclosing something of little value, which stifles innovation instead of fostering it.
Given the current IP system in the United States, I can't fault companies for investing in patents, software or otherwise. However, If I were an U.S. Citizen, I'd certainly be lobbying for Patent reform.