I just wanted to voice the contrary opinion before all the "THE MOTLY FOOL SUX" posts start rolling in.
I've followed The Motley Fool since their AOL days, and then became a member of one of their subscription newsletters in 2003. Currently, I subscribe to several of their services that span the range from value, growth and income investing.
To the OP, I am not sure if you were making a tongue-in-cheek comment, but just in case others were confused by your post, the article that you linked wasn't really saying that people should wait to retire by 73, it was more about the value of time when compounding your interest. The author could have picked 45, 55, 65 or 75 and the point of the lesson would be the same (refer to the graph in the article). It's just that the 2nd saver started at 40 years old, so giving him 33 years seemed like a good time frame to amass wealth.
I agree this is pretty much standard fare, and most of the free articles that are available on the site are on par with other articles you can find on any site with personal finance advice such as Marketwatch, CNN Money, etc.
From the early days, the mantra of The Motley Fool has been to support DIY stock picking, and over time, they have tried to build a business that gives individual investors the resources and information to do just that. When you sit down and think about it, it is actually a really difficult task to try to build something that can be of value ot people of all investing experience levels, investment philosophies, risk tolerance and net worth.
I have profited from many of their stock picks that have been recommended over the years in their various newsletters. I don't blindly buy/sell based on their advice. I look at their recommendations and try to find the ones that I can understand. I find ones that are appealing to me, discuss it with my wife, and try to get a handle on the valuations before buying. Sometimes my slow pace causes me to miss a buying opportunity, sometimes it gives me a buying opportunity. Over time, the process has worked for me.
The most valuable part of the subscribing to the newsletters is that the stock picks have been previously vetted, so it greatly narrows down the universe of stocks into a manageable number that I can process myself. I don't believe that The Motley Fool is the only reliable game in town, but in general, the philosophies championed by the advisors are in line with my own investment style.
The other thing I like about the paid subscriptions is access to the message boards. When a stock pops or when it drops, there are usually thoughtful posts by the bulls and bears. Both sentiments are welcomed, as long as there is a healthy debate and it doesn't degenerate to a "you suck" "no, you suck" situation. With other sources like Yahoo Finance, it is often difficult to sift past the noise when I am looking for information.
I would argue that The Motley Fool has vastly improved from their early days. They have learned a lot, and are willing to admit their mistakes while trumpeting their successes. If you read through some of their early work, some of it is truly cringe-inducing, eg., The Dogs of the Dow strategy comes to mind. I don't think they will ever live this down, seeing as it is immortalized in print, in The Motley Fool Investment Guide.
Anyway, I am a satisfied "Fool." I have never had the expectation that I would get rich quick following their stock picks, but I do believe that using their site to interact and learn about the investing process has made me a successful investor. Their investing philosophies align with mine and over time, I have found value in their services.