Systemd certainly seems to divide opinions. This “new” init system, which also seeks to be a daemon and a central building block of the Linux today is without a doubt both good and a bad thing.
The good thing about systemd is that it does provide some much needed new functions and keeps things well within “the one single cover”. However, since systemd tries to be very versatile its design also tends to evolve more complex every time a new version gets done. Complexity by itself is not a problem when things do not break and everything goes well. The reality of computer world is however that things do, in general, break sooner or later and in this regard systemd is not perfect. For example: My more powerful computer was able to boot Debian Jessie easily but my Intel Atom build greeted me with a message saying that Systemd malfunctioned – and nothing ended up working. From the previous example it is easy to see that systemd (like all programs) do get bugs which can really ruin the user’s experience.
Whatever you think about the design of the program in question there does however exist a far more grave aspect to consider. Things as they now appear are hinting towards the case that systemd is becoming THE big default, which will be soon in almost every corner of the Linux world. Personally, I find this to be very disturbing. Take for example Debian: systemd is already being marked as a dependency package for many essential core parts. In the future this might mean that you could actually need to rebuild major pieces of Debian’s base from source in order
to get to the point where the os could live without systemd.
The wide adoption of systemd has certainly made many people angry – Even to the point that there is an actual website about the removing systemd: http://without-systemd.org/wiki/index.php/Main_Page
So, at best systemd is controversial and while I am personally against its wide adoption – since it might actually kill the competition and some other prominent init systems if it becomes the sole focus of development – I must admit that the development team has done impressive work in promoting and putting this new init system together.