Starting on June 1, 2012, the My Trips Facebook app will no longer be available. This is because Facebook will stop supporting a technology, FBML, that My Trips is built with. Because My Trips is just a fun little side project for me that I did on the site, completely outside of my regular job, and the usage of My Trips is very low, I can't justify spending the time that it would take to redesign My Trips with a supported technology.
In a nutshell, FBML allowed me to pretty quickly create My Trips without having to specify font sizes, colors, etc. Things like the tabbed look of My Trips are possible with a very simple FBML command. When I started work on My Trips in 2009, Facebook was promoting FBML as one way to create Facebook apps. Had it not been for FBML, I probably would not have created My Trips. However, in 2010 Facebook started discouraging the use of FBML. I suspect this is mainly because it uses too many resources on their servers. I don't agree with Facebook's decision to completely abandon FBML, however, as a a software developer I can understand why they would abandon it.
I'd like to thank everyone for using My Trips over the years. If you know of any Facebook apps that provide similar functionality, please post a comment here!