CS6 is coming soon. Adobe said as much a long time ago pointing to a second quarter launch. Additionally, in case you hadn’t heard, you can buy CS5.5 now and get a free upgrade to CS6 when it ships.
There has been no specific date announced yet.
I placed my order today for a 12 month subscription for the CS6 Creative Cloud. This costs £27.34 inc taxes per month in the UK. This is special price for existing customers. Adobe confirmed that the estimated availability is Monday 7 May.