If I'm using cgminer (version 1.5.1) then i see a lot of:

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[2011-07-27 18:13:25] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:13:25] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:13:38] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:13:38] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:13:38] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:13:41] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:13:41] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:13:41] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:13:47] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:13:47] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:13:47] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:14:05] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:14:05] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:14:05] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:14:20] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:14:20] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:14:20] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:14:22] LONGPOLL received after new block already detected
[2011-07-27 18:14:22] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:14:22] LONGPOLL received after new block already detected
[2011-07-27 18:14:22] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:14:22] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:14:49] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:14:49] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:14:49] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:14:53] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:14:53] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:14:53] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:14:58] Accepted 3d22e40b GPU 0 thread 0
[2011-07-27 18:14:58] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:14:58] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:14:58] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:15:34] Accepted 1f24ab65 GPU 0 thread 0
[2011-07-27 18:15:34] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:15:34] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:15:34] New block detected on network before longpoll, waiting on fresh work
[2011-07-27 18:15:46] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:15:46] LONGPOLL detected new block on network, waiting on fresh work
[2011-07-27 18:15:46] New block detected on network before longpoll, waiting on fresh work
...