Google gave a biggest visual change to keyboard with the release of Android 5.0 Lollipop. The keyboard have been almost the same since the release of Honeycomb. With Lollipop not only keyboard but all apps have a new look. The Material Design presented by Google seem to be preferred by almost all Android users.
The keyboard is the only app in your phone you can’t replace. The new keyboard with material design has a beautiful look but you may not like the input method. So you have to wait for third-party keyboards.
Android Lollipop is becoming very popular. Numerous devices are receiving it officially or non officially, but it looks like people are falling in love with Lollipop, so developers are updating their apps with the New Material Design look.
SwiftKey has already presented Material Design themes in the past, but now it brings 5 more. In the newest theme you can get 3 new colors to work with: Material Orange, Material Pink and Material Phosphor green.
Also there are available the Material dark and Material light which look more like the standard Lollipop keyboard because they lack the boundaries that SwiftKey has added to its themes.
Unfortunately these themes are not free. You can get each one only for 99 cents or pay $2.99 to get the entire pack. Download them on SwiftKey (Playboard) | SwiftKey (Play Store)