According to Microsoft, the Wunderlist team will continue to add popular features from Wunderlist to To-Do, including list sharing, but eventually Wunderlist will be retired. Specifically, Microsoft said, "Once we are confident that we have incorporated the best of Wunderlist into To-Do, we will retire Wunderlist." There was no timeline given, nor exactly what features or even how many of the features from Wunderlist would make it into To-Do, though.
Wunderlist is an incredibly full-featured app that is beloved by many and has been one of the best to-do apps on the market for a while. But, Microsoft did buy the company and the team behind Wunderlist, and apparently, Microsoft thinks it is a better idea to have the team build a new app from scratch rather than continue to improve upon Wunderlist. Given how limited the functionality is in To-Do right now, we'd say there's a good amount of time before Wunderlist is officially retured, but we can't say for sure.
We'd hope that at the very least, once Microsoft does get To-Do to where it wants it to be, there will be some sort of option for remaining Wunderlist users to transition smoothly to To-Do. In the meantime, if you're a Wunderlist user, what's your plan? Will to move to a different to-do app now or wait to see what Microsoft does with To-Do?