It will be available on January 29 for purchase at a price of $19.99. For those of you who do not know, Bayonetta was released back in 2009 to much critical acclaim.
Although Platinum Games have brought the original to PSN, keep in mind that the sequel, Bayonetta 2, coming out this year, will be a Wii U exclusive and so far there has been no word on whether it will ever be available on any other platform.
It seems unlikely that it will be released on other consoles though, as Nintendo is the publisher and in a statement Platinum Games made it clear that without Nintendo Bayonetta 2 would not have been possible.
Check out this link for the making of Bayonetta 2.