is it just the bloomberg app, or is it others?
this is quite a common problem, which normally affects all apps. the two solutions generally suggested are a reset of the ipod (hold down home and power button until you get an apple on the screen) or downloading another app (any seems to do it)
if you downloaded it via your computer, have you tried downloading it straight to you ipod using wifi? or have you tried deleting it and downloading it again?
if it is just that app, it may be a problem with the update, in which case it may be a good idea to contact the manufacturer/go to their website and see if any problems have been reported in any forums they may have.
another thing i've just thought of, and i'm not sure whether this will work, but when i go into the apps folder via mymusic and itunes, (on a windows machine, not sure about mac) there are usually multiple versions of the same app listed if they've been upgraded. you could try deleting the most recent one and then resyncing.