CCP has posted new information on the Updates page to let players know that the "Mosaic" patch will be deployed on Tuesday, April 28th.
Among other things players can expect the following:
- new permanent ship skins
- the overhauled new player experience
- the new 3D star map
- Serpentis & Blood Raider missions
- new assembly effects for anchorable structures
- T3 destroyer rebalance
- new control tower forcefield effects
You can read about each of these on the EVE Online update site.