Up till v22 (May 2008) the catalogue icon had tabs. A relic from the past. The catalogue in 2000 untill, well, we don’t know exactly, had these upper tabs. We sorta rebuild it, you can click around in below catalogue. Navigation in general works, sometimes clicking a section gets you a second page. It’s there to serve you an impression, nothing more. Real catalogue behaved a little different and this is actually a mixture of 2001 and later screenshots.
The catalogue that replaced the old (April 2003) still looks a lot like current one. When it comes to functionality, tabs were moved to the right, smaller, so easier to find, and real-size previews were added. This version of the catalogue stuck around for close to 7 years.
When in May 2009 the private, soon public BETA started, it slowly evolved to current catalog (?!). Experiments with colors and some more made it wildly unintuitive, but in the end they settled with something that works. Most changes are not that visual, but functionality changed drastically.