Xposed Framework is already available for Android 5.0 Lollipop thanks to developer rovo89.
Now you can enjoy all the features of Xposed Framework on the last Android version. The installation is slightly more difficult than it was on Android 4.4 KitKat, but all the steps are clearly described on the XDA-developers' forums.
Xposed Frameword offers you more customization options than you could get with any custom ROM. Xposed works with modules, each one created to modify the UI of your device. You can get check the list of modules and download the ones you want from the Xposed repo site.
With Xposed Framework, it's easy to configure the stock ROM as you can install the modules that best suit your needs. It requires no flashing of any ROMs, but brings tons of customization and tweaks that you can install like apps on rooted devices.
Keep in mind that you need a rooted phone to install the Xposed APK. If you want to give it a try but don't know how to root you phone, you just need to follow this guide, choosing the correct manufacturer and model for your device.
This is an alpha version, so you can expect to have some bugs. If you are not confident enough to try it, wait a little until the stable version is released. However, if you are already familiar with Xposed Framework and want to give it a try, you just need to be on a Lollipop ROM and flash the zip file that you can download from XDA.
Currently, there is only available for ARMv7, but 64-bits version will come soon. Most of the modules available for KitKat should work fine on Lollipop.
If you like to customize you smartphone or tablet, you are surely going to enjoy Xposed Framework.
Source: AndroidPolice.