Both Westlaw and Lexis plan to unveil new platforms this year (Westlaw's will appear first). Both have been designed to be easier to use. This marks a big change for both systems, and it is partially a response to newer competitors like Fastcase and Bloomberg.
This ABA Journal article does a good job of explaining this situation.
Hopefully the new Westlaw and Lexis platforms will not be much more expensive to use than the current systems.

Ernster, the Virtual Library Cat