The place where I've used it are mainly on the data warehouses with larger implementations, and having everything in one enclosure is really a lot nicer. Having the disk, all the memory, and all the networking, makes not just the implementation easier, but as you're running it, a lot simpler to administer. Because we're asking it to handle everything, it's a simple solution to administer and support. It also has plugins that makes it easier to monitor.
Improvements to My Organization:
Definitely having the ability to have one machine do everything has been the biggest improvement for us organizationally. From the administration side, it helps. If one or two admins can handle it, they don't have to go all over the place to, such as to the storage team, the network team, or anywhere else because they can do a lot of things internally. Definitely, we've seen cost, time, and HR savings with several implementations.
Room for Improvement:
Sometimes pricing can be a bit of an issue, especially if customers don't know exactly what they're getting. Maybe they've gone through the whole process and they didn't get the right size or the right amount. I've worked with several customers who had implementations that were too small and then had to upgrade, as well with others who were overpowered with their implementations.
The deployments have been issue-free.
We haven't really had any stability issues. The experiences we have had were when there have been hardware failures, but a Oracle took care of that pretty quickly. Our customer had databases and memory modules die and everything kept running. With the failures we've seen, it's stayed very consistent on the ones we've done.
If it's done with the right specs in mind, it seems to scale pretty well. We haven't really had any scalability issues.
Exadata is pretty much set up when it ships. Afterwards, you just have to copy data over and it's ready to go. So the setup is fairly easy and straightforward.
Definitely do a POC on it. Work closely with Oracle Professional Services to help you with the right configurations.