no.Can BR's have a CD layer?
technically speaking, BD-A can be seen as slightly improved DVD-A. it retains similar universality in regards of abilities
to deliver to end user multiple formats (surround /stereo HiRez sound, video, additional content such like lossy/lossless
audio formats for use on portable gadgets... etc.)
my guess is that this UMG initiative are nothing else but attempt to consolidate delivery of entertaining stuff on the single
universal phisical medium. considering commercial failure of previous attempt of competing DVD-A and SACD formats due to
their incompatability and lack of massive support from hardware manufacturers, BD-A (albeit most likely will never hit the
hight of CD's sales in past) yet have potential to sustain sales of phisical medium on condition that 2 other major players
will got involved in this game.
in such case there would be only one competitor - purchase of downloadable single track, which is as of today, most popular
form buying of music.