Hi Rupesh,
Better go for SP10 it is having lot of new feature in all aspect.
check the below discussion
Re: SPS 09 Availability and new features
Also check the http://service.sap.com/rkt-solman
SP11 will release on March 2nd week check the link for SAP Support Package Stacks Maintenance Schedule
https://websmp210.sap-ag.de/~form/sapnet?
_FRAME=CONTAINER&_OBJECT=011000358700000294692004
Rg,
Karthik