I've been working with the SQL Server on Linux (SSoL) version for quite some time, almost a year. In all of that time, I've for the most part found that SQL Server is SQL Server. When I connect, run demos, check code, almost everything just works. If I didn't bother to check @@version, this would appear to be just another SQL Server to me. That's what a new video on Channel 9 shows as well. SQL Server is pretty much the same on both platforms. I've tested the Redgate tools and to all of them, SSoL is just SQL Server.
There are some differences, which is to be expected. Any operations that access the file system and require paths work a bit differently, and for those people that end up administering the product, there will be some changes to get used to. The advanced HA features are similar, but again, some work is required. However, this isn't all bad. I'm impressed with the apt-get process (I'm testing on Ubuntu), which is way, way easier than any patching or updating process I've gone through on Windows. In fact, setting up an Ubuntu VM last year was easy, and installing SQL Server was about as easy as it could be.
The tooling on Linux isn't as mature, and I don't know when we will see a GUI client, but as I move more and more to PoSh or scripting to make changes in SQL Server, I expect more and more people to manage both Windows and Linux versions in the same way. Certainly using SSMS to write queries is a much nicer experience, and I would guess that many developers that might run SQL Server on OSX or Linux will want a Windows VM for SSMS. Of course, since Visual Studio is now on OSX, maybe we'll see SSMS running natively on other platforms.
I don't know how many enterprises will run SQL Server on Linux, but I'm sure there are some that will. I don't think a lot of organizations will move from Windows to Linux, unless they have loved SQL Server enough to install a single Windows host for the database and want to get rid of it now. I do think lots of developers will run SQL Server on Linux/OSX, especially in containers, where it is really easy to get a container running on their platforms.
If you've experimented with SQL Server on Linux, or you are excited, let us know. If you think your organization might use this platform, let us know as well. I suspect a few of you will just because you can, which is as good a reason as any.