On all the Wikimedia Foundation projects you are invited to "try beta". When you do, you will make use of the experimental changes made by the Usability Initiative. These changes already make a big positive difference.
In the evaluation of the feedback from the beta test, it was found that many people leave the beta when they use a language that is not fully localised. These messages are best localised at translatewiki.net and with LocalisationUpdate now implemented on all WMF projects you will find that localisations are typically available within two days.
When a lack of localisation is no longer an issue, we may find the problems with the software that a developer can deal with. It is for this reason that we ask you to localise these messages. When you are not involved in translatewiki.net yet, please create a user, tell something about yourself on your user page and ask for translator rights.