The plan is an ambitious one: YouTube wants to bring all of the power of its content creation tools to mobile devices. However, it sounds like to start it will just be a standalone app to help creators manage their channels and get easy access to comments and analytics. It is unclear if the video editing tools will be in the first release, but YouTube is working with creators to find out what features are most important, and where it needs to focus its efforts.
Of course, creator tools are a nice way to make people happy, but a much better way is giving them more options for making money. Right now, the vast majority of revenue for creators comes from ads, but YouTube is working on some interesting ways to allow for more revenue generation for creators (and likely YouTube itself). YouTube has mentioned that it is looking into various ways, but two stand out. First is a plan to allow creators to ask for donations directly. This is presumably to bring donations into Google's ecosystem, and setting up something (likely Google Wallet) to compete with options like PayPal and Subbable.
The other option is one that no one saw coming: revenue sharing on royalties for musicians who perform covers or make remixes and mashups on YouTube. The music community on YouTube has always had a strained relationship with the Recording Industry Association of America (to be fair, a lot of groups have had a strained relationship with the RIAA). So, if YouTube has found a way to let its creators share in the revenue there, it could be a big change for the platform.
No word on when the changes or the mobile app will come. YouTube is still in the process of getting feedback from creators on what features are most important to have in the app.