No new features for VrayScatter planned. But it will be supported and updated for all new versions of 3dsmax and Vray.
If you have purchased VrayScatter in 2010 - you can migrate to MultiScatter for free
If you have purchased VrayScatter before 2010 - you can migrate to MultiScatter for 50% of MultiScatter price.
You can use VrayScatter and MultiScatter in same tine in one project.