Hello Brantz, 

Mark Spam has been removed. After the removal of Bayesian Filtering, this button would only move the message to the Junk Email folder. For managing your emails, you'll now have options for Block / Unblock Sender and Trust / Untrust Sender. When you block a sender, it will add the sender's address to your Blocked Senders list (which can be found in Spam Filtering) and perform the block sender action on the selected emails. You can modify your block sender action to move messages from those senders to Deleted Items or Junk Email or to delete them outright. (I believe the default action will be to move them to Junk Email.) 

You also have email options for Create Filter or Add Sender to Filter. These act as shortcuts to create a new filter for similar messages or to add a sender's address to an existing content filter. 

I will ensure the documentation is updated to reflect these changes. Please let me know if you have any questions!