Twitter follow limit?

[Ian]

Every account can follow 2,000 users total. Once you’ve followed 2,000 users, there are limits to the number of additional users you can follow. This number is different for each account and is based on your ratio of followers to following; this ratio is not published. Follow limits cannot be lifted by Twitter and everyone is subject to limits, even high profile and API accounts.
If you've reached the account-based follow limit (2,000 users), you’ll need to wait until you yourself have more followers before you can follow additional users. Follow limits are system-wide; Support cannot remove or adjust your follow limits.
To follow one or two additional users, unfollow a few accounts you're currently following.