I'll go with the few saying that, for now, there's no great alternative to Rapidshare, and there are still a lot of users with premium accounts that still have to run out, so for now there won't be much of a drop-off. We'll be seeing what the situation is like in a few months.
Rapidshare has a history of changing download limits up and down - at times even removing limits completely:
Quote: On June 3, 2008, RapidShare redesigned their website. Premium users can now download up to 50 gigabytes of data within five days; doubling the quota from the original 25 gigabytes per five days.
On June 26, 2008, the maximum download per premium user was further changed from 50 gigabytes per five days to 10 gigabytes per day. At the same time RapidShare limited the number of IP addresses that can download from one account to one.
On July 2, 2008, the maximum download limit was modified yet again. Each premium user gets 10 gigabytes of download bandwidth per day but any unused bandwidth is saved or rolled over to the next day. There is a limit of 50 gigabytes total that can be saved through this method. There is no further need to enter CAPTCHA codes in free service. In addition, free-users can now upload and download bigger files (up to 200 megabytes).
On July 21, 2008, the maximum download limit was modified due to excessive traffic. Each premium user gets 4 gigabytes of download bandwidth per day with a maximum of 30 gigabytes that can be accumulated if not used.
On July 30, 2008, the maximum download limit was increased from 4 gigabytes of download bandwidth per day to 5 gigabytes.
On September 2, 2008, "a Premium Account allows the download of 10 Gigabyte (10.000.000.000 Byte) per day, any unused bandwidth can be rolled over up to 50 gigabytes."
On October 23, 2008, "a Premium Account allows the download of 80 GB per month or 2.66 Gigabyte (2.660.000.000 Byte) per day" making it one of the lowest in the industry. Already existing Premium Accounts continue to receive 10 GB per day for as long as their account was paid for before the change.
I'll be on the wait... who knows what is still to come.