What can you do with it? You can: create and consume web services; perform database CRUD operations; get/send files over FTP/SFTP; read/write JMS queues; read/write to file systems (Linux, Windows, Mainframe, etc.); send/get email; read/parse/create EDI; etc. Nearly everything you do in an IT shop to integrate systems and applications you can do via Boomi.
Boomi isn't ideal for everything. E.g. complicated ETL, voluminous file transfers, complicated processing, etc. But for the everyday IT tasks, Boomi is the perfect middleware tool.
Simple tasks can be done in minutes with Boomi: read from a database to create a report and email it; call web services; web-service enable an existing process; create an enterprise web service that orchestrates a process; poll directories looking for files; poll JMS queues looking for messages; copy data between two applications; convert data from one format to another; in short - anything involving integrations between systems or applications can be done in Boomi.
Boomi doesn't replace all of your tools - but it replaces 80% of what you do with those tools and it takes 20% of the time to do it. I'm convinced that it's the future of traditional IS development.
Ease of use, simplicity of the programming paradigm, and the vast capabilities of the product.
It doesn't implement everything in a given spec (e.g. I can't access the full request/response for a web service call; I can't use all features of standard functionality like SMB; etc.) The tool needs to mature a bit more so that it can be leveraged more in a variety of enterprises.
Value for money
Ease of use
Likelihood to recommend: 10/10