24 hour time in guest requests
Personally, I love 24 hour time. There are 24 hours in 1 day, and so let's all refer to each hour as it is sequenced within the day. I realise 24 hour time is is well known in Europe, but this isn't the case in many other parts of the world.
Unfortunately, many of our guests struggle with the 24 hour format. And so I frequently get check-in requests at 2:00, 6:00 etc... I find myself confirming these times with the guests, and more times than not, the guest means to request a late check-in in the evening rather than an early check-in.
I have not seen the guest user interface for the special request selection, however I'm guessing it's a text input field which auto completes based on the time entered. Perhaps this interface can be improved for the 24 hour challenged? Maybe the am/pm equivalent could be displayed in brackets. The alternative is to modify the time input format using internationalisation rules and the default time format could be modified based on the location of the guest?