SCEE's just confirmed on Twitter that Mass Effect 2 is now available from the PlayStation Store.
May want to clear room on your HDD if you buy it, though: it's 12Gb to download, with the game requiring 24Gb on your HDD, apparently.
The download costs €60, or £48 in the UK.
Of course, you could buy it for £8/€6 if you have a 360. Otherwise, if you're mental enough to download from the PS Store, go for it.
The title made it into number seven in this morning's UK charts.