On the 14th of May we can expect the launch of the Radeon HD 2900 XT, this card will be immediately available but will only be able to match the speed of the GeForce 8800 GTS. On the same day we can also expect the launch of some Radeon HD 2400 and Radeon HD 2600 variants but that will only be a paper launch as the first of these cards are expected to appear on the market in June.
The RV630 and R610 won't get into production till late May. The samples are out, but the samples are not based on the final A14 silicon. ATI is now approximately four weeks behind its original agenda.
The original plan was to launch and have RV 630 and RV610 available in volumes in the end of May. There might be some cards but the real volume production and availability is expected in late June now.