Topsyの検索結果が少ないと思ったらメンテナンス中だった

Index maintenance and fresh results only mode from Feb 18th to Feb 22nd. - Topsy Service Status

This maintenance operation that will start Feb 18th at 9AM PST and is expected to finish within 96 hours. During this maintenance window, search queries will be answered by a fresh index that is based on tweets posted after Feb 17th 2011.

日本時間の2011/2/19深夜2時に始まり、予定通りなら2/23の深夜2時に終わるということか。