what flags did you use for guiminer and what parameters are you setting in cgminer?
how are you overclocking?
edit: oh and how long had you been mining when that hashrate was showing on deepbit, most pools average shares returned over a time period to guess your hashrate, it can take 10mins or longer on some pools to show full rate.
cgminer.exe --url=pool.50btc.com:8332 --userpass=########### --intensity 8
i am using msi afterburner to overclock my 6670?
i checked it even after an hour the max it goes is 60Mhash