Gary Wolf at Wired has an indepth feature on Craigslist called ‘why craigslist is such a mess’. It

The Internet’s great promise is to make the world’s information universally accessible and useful. So how come when you arrive at the most popular dating site in the US you find a stream of anonymous come-ons intermixed with insults, ads for prostitutes, naked pictures, and obvious scams? In a design straight from the earliest days of the Web, miscellaneous posts compete for attention on page after page of blue links, undifferentiated by tags or ratings or even usernames. Millions of people apparently believe that love awaits here, but it is well hidden. Is this really the best we can do?
Odd perhaps, but no odder than what you see at the most popular job-search site: another wasteland of hypertext links, one line after another, without recommendations or networking features or even protection against duplicate postings. Subject to a highly unpredictable filtering system that produces daily outrage among people whose help-wanted ads have been removed without explanation, this site not only beats its competitors—Monster, CareerBuilder, Yahoo’s HotJobs—but garners more traffic than all of them combined. Are our standards really so low?
But if you really want to see a mess, go visit the nation’s greatest apartment-hunting site, the first likely choice of anybody searching for a rental or a roommate. On this site, contrary to every principle of usability and common sense, you can’t easily browse pictures of the apartments for rent. Customer support? Visit the help desk if you enjoy being insulted. How much market share does this housing site have? In many cities, a huge percentage. It isn’t worth trying to compare its traffic to competitors’, because at this scale there are no competitors.
Each of these sites, of course, is merely one of the many sections of craigslist, which dominates the market in facilitating face-to-face transactions, whether people are connecting to buy and sell, give something away, rent an apartment, or have some sex. With more than 47 million unique users every month in the US alone—nearly a fifth of the nation’s adult population—it is the most important community site going and yet the most underdeveloped. Think of any Web feature that has become popular in the past 10 years: Chances are craigslist has considered it and rejected it. If you try to build a third-party application designed to make craigslist work better, the management will almost certainly throw up technical roadblocks to shut you down.
Craigslist is not only gigantic in scale and totally resistant to business cooperation, it is also mostly free. The only things that cost money to post on the site are job ads in some cities ($25 to $75), apartment listings by brokers in New York ($10), and—in a special case born of recent legal trouble—advertisements in categories commonly used by prostitutes, because authorities encourage vendors to maintain a record that would aid investigators. There is no banner advertising. They won’t let you join them, and at this price you can’t beat them either.
It is not a very complimentary look at Craigslist, but it somehow leaves people, particularly the web entrepreneurs, with a feeling of admiration for the company and its founder Craig Newmark. I have listened to Craig on multiple occasions. His talk gets boring after the first time but he remains quite charming becuase he is different from most people you meet in Silicon Valley and he is sincere and he has singlehandedly changed the US classifieds world.
The article is very well written and is an interesting read. It makes some valid points but misses the target on what makes craigslist tick. Craigslist is quirky. It goes out of the way to emphsize its function over form. It goes out of the way to avoid making boat loads of money and hiring a lot of people and become all ‘corporate’. But that is their USP. That is their brand identity. That is the secret behind its success. If it was not like that they may not have become the powerhosue they are today without gaining much public resentment that comes with success. If they got all ‘corporate’ and ‘professional’ and try to maximize their revenues, they would have ended up another ebay. Who knows?