A whole lot has changed since 2008. You missed the sale over the Christmas holidays, so the prices are a little more expensive than they were.
You can see your options by clicking -->
HEREIt looks like your choices are either:
BIAB Pro for $79This is just the basic program. If you install over your 2008.5 version, you'll still the styles that were available at the time; however, the Pro pack is just basically the main BIAB and RealBand application, but only a handful of styles, RealTracks, and RealDrums. You get 30 RealTracks in 9 bands and 1 RealDrums set, MIDI Supertracks sets 1-3, MIDI Styles Sets 0-3 and other assorted styles, MIDI Soloist set 1, MIDI Melodist set 2, Loops set 1, and the Bonus RealTrack (classical string quartet).
MegaPak for $159This includes a little more than the Pro version. In addition to BIAB and Realband, you get 160 RealTracks in 36 bands, Realdrums sets 1-6, MIDI Supertracks sets 1-6, MIDI styles sets 0-77, MIDI Soloists sets 1-11 and 16-20, MIDI Melodist sets 1-8, Loops set 1, and the Bonus RealTrack (classical string quartet).
UltraPlusPak for $299If you can afford it, I would recommend getting this version. In addition to BIAB and Realband, you get RealTracks Sets 1-205 (each set includes several RealTracks), Realdrums sets 1-29, MIDI Supertracks sets 1-17, MIDI styles sets 0-77, MIDI Soloists sets 1-11 and 16-20, MIDI Melodist sets 1-8, Loops set 1, Artists Performance sets 1-5, and the Bonus RealTrack (classical string quartet).
EverythingPak for $399This includes everything in the UltraPlusPak, plus the Video Tutorial Pak and the Artist Performance Sets 1-5.
At the bottom of the link I provided, there is a nice chart that indicates what is and is not included in each package.