In a parallel universe where it is still 1999, yes.
Search engines have become far more sophisticated since the early days. We can especially thank Google for this major change. Since they are now the most common search tool, and at the forefront of web analysis, what Google does most will follow. And Google says hiding a list of keywords in the same color as your background is a no-no. To see authentic results in a search engine, you must be using the correct words authentically. (See Google’s policy on this topic) Content is king.
(Side note: Years ago I remember starting to purchase vitamins online and at the bottom of the page was a giant block of emptiness. It seemed a little odd and, on a whim, I opened up the “view source.” There, at the bottom, was an enormous list of words that had absolutely nothing to do with the company, vitamins, or even health. The web master had simply found a list of the 100 most commonly-searched words which, of course, included a dozen pornographic words. As my son would say, “Cheater, cheater, pumpkin eater.”)
Now this leads us to the more interesting issue: what ARE my keywords?
To answer this, you absolutely must step out of your business brain and into the minds of your visitors. What do customers call your product or services? What are they looking for? What is another name for what you do or sell? You might be an attorney, but people search for lawyers. Your store sells adhesive tape, but my wife wants scrapbooking glue. The post office calls it postage, but I usually buy stamps. Once you have developed a comprehensive list of words and phrases that people use, work those into the actual text of your pages. Use them in the headlines, sub headlines, and picture captions. Don’t try to trick the search bots–beat them at their own game. Be sure to use Web Analytics to validate your keyword research and content.
There are many free tools and tutorials out there to help you understand SEO, keywords, page rankings, etc. I have added a dozen articles on this topic in my Chatter links. If you sell something, it is also a good idea to check out eBay. I know that sounds like an odd suggestion, but think about it: ordinary people sell their items on eBay and they are the best at describing ordinary things using ordinary language. Their listing titles pack in as much information as humanly possible in order to cover all of their bases.