The Servlet 3.0 Specification (JSR 315) will be an update to the existing Servlet 2.5 Specification.

Potential considerations are:

• Web framework pluggability.
• EoD (Ease-of-Development)
• Asynch and Comet support
• Security
• Alignment
• Misc

All in all it seems sensible. A great technology taking a step further. See the JSR for more details.