Looks like sony finally changed the Xperia S to SL, the company has launched a similar device with dedicated ICS style buttons and a paster processor, overclocked perhaps. The Xperia SL is a slight refresh of the S, it has an additional duo of color choices (silver and pink), a faster dual-core 1.7 GHz Snapdragon S3 CPU and Android Ice Cream Sandwich (up from a 1.5Ghz processor and Gingerbread).
Apart from the above changes you have the same HD 720p display, 12.1 MP camera and 1080p video with anti shake. No details on pricing or availability in India. You can look at our Xperia S Review or the Xperia S ICS update for an idea.