With regards to the Switch, Gamefly had stated previously that they had no plans to offer Switch games for rent. This was not due to any lack of desire to work with Nintendo, but rather due to not having heard anything from the Big N. However, the situation has since changed and Gamefly has heard back from Nintendo.
The company responded to a fan on twitter, by revealing that now that they have heard back from Nintendo, they plan to offer Switch games for rental purposes. Gamefly will have a full database of available games starting tomorrow, although they did not specify a time. This is great news for Nintendo as they need to be able to get their games out to as many people as possible. Having their games available through Gamefly is a great way to get this done.