IBM are big in the OASIS group that specified the standards by which OpenOffice works; In some areas OpenOffice is seen as IBM's baby, and the press believe that IBM are using OpenOffice as a stick to beat Microsoft.
OpenOffice, MySQL and Java are the things that will definitely survive.
I kinda hope that Solaris will continue and that AIX apps will be ported to it because Solaris is more mature and has more development (especailly with ZFS), especially since OpenSolaris has a PowerPC variant now, but that may be my wishful thinking.
Problem with ZFS though is that IBM sell raid and storage solutions and ZFS does all that for free ... IBM might not like that hanging around ... Only thing in it's favour is that ZFS will hurt the competition too.
One thing not mentioned (we have an ex-sun employee in our office, and he still likes Sun, but not the atmosphere that currently surrounds the place;) Sun still have 3 Billion in cash reserves, so if IBM buy it for 6 Billion they're getting a very good deal.