As a wise man once wrote, "Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is." This may help explain the post on the RSI community forums by Cloud Imperium's Jeremy Masker, who explains that the client for Star Citizen is going to be extremely large, and the game's patches are likely to be bigger than most games (thanks DSOGaming). For those looking for more on the game, you now can view its PAX East presentation online. Here's word on what to expect when it comes to file sizes in the upcoming space combat game, correcting speculation that the client and patches would be considerably smaller:

As I have already said, I would not count on this. The game compression and asset removal is unlikely to yield such high gains that we will be able to reduce our client size to 30-40gb. The size and number of assets that are left to deliver means that our client size is much more likely to be 100gb.

Also, yes we are optimizing game patching for speed and to only deliver diffs, but this is unlikely to reduce actual patch size. Again, each patch has 100s of assets, each of these assets are at times 200mb, this leads to 2-6gb patches, and if we end up doing a file type re-factor and have to re-download 30-40% of the assets on the hard-drive, then the patch will be 14-20gb.