Prompt window flicker and sluggishness in v0.5

When using the Ubiquity prompt to look up a command, those commands with favicons tend to flicker randomly slowing down the UI. Typing takes longer, updates take longer and command lookup is exceedingly slow. So much so that I find myself needing to wait 2-3 seconds for the proper command to be found, even after having typed it. In certain circumstances, opening Ubiquity, typing something in and then hitting return provokes no action because Ubiquity has not had enough time to do process everything. Neither of these were issues in previous Ubiquity releases.