What you need when you are solving a business problem is the context, you need to be able to share the data, the customer order, the invoice, the asset - whatever is involved. You also need to know who has the authority and knowledge to work on any particular problem
Mingle allows you to follow everything, every business object, every customer, every piece of equipment. If it is a separate platform, no-one has the time to sit there and chat all day
Mingle isn't a replacement for email, it is just a better way to get your work done because it gives you the full context of information and transparency in your processes.