The 24-year-old former Everton and Bradford forward made just one appearance as substitute in the Carling Cup win over Swindon for Leeds but will go straight into the Blades squad for Saturday's trip to Brighton.
"Danny is a very positive player," said Blades boss Neil Warnock, who has also completed the signing of Italian defender Emanuele Gabrieli. "He is direct, strong and I like all his aspects.
"I first made an enquiry for him when he was at Everton, but they wanted too much. With Leeds signing (Brett) Ormerod I knew he would be surplus to requirements so I spoke to Kevin Blackwell."
"Danny is a very positive player," said Blades boss Neil Warnock, who has also completed the signing of Italian defender Emanuele Gabrieli. "He is direct, strong and I like all his aspects.
"I first made an enquiry for him when he was at Everton, but they wanted too much. With Leeds signing (Brett) Ormerod I knew he would be surplus to requirements so I spoke to Kevin Blackwell."