The former Reading midfielder joined the Swans in January and has played a key part in the recent run of strong form that has catapulted them to eighth in the Barclays Premier League table, and all but guaranteed top-flight survival.
The 22-year-old Iceland international has grabbed five goals in his nine appearances, including doubles in the away wins at Wigan and Fulham, and Rodgers is a keen admirer of the player.
It had been suggested a club-record fee of around £6.5million would be enough to make the switch permanent, but Hoffenheim are thought to be keen to have Sigurdsson back among their ranks come the start of next season.
And Rodgers said: "He is still a Hoffenheim player. He has had a wonderful effect on the group and I know he thoroughly enjoys it here, but we have been unable to sit down and discuss anything so until that happens then the situation remains the same.
"He is a loan player who is benefiting from playing with a wonderful group of players and we are benefiting from his qualities.
"We can see he fits perfectly into our style and we complement each other well but we will see what happens between now and the end of the season."
But two players who could be about to extend their stays at the Liberty Stadium are Leon Britton and Scott Sinclair.
Britton, 29, has been outstanding playing in his deep midfield role this season, with his passing statistics holding comparison even with the likes of Barcelona's Xavi and Andres Iniesta.
Winger Sinclair, meanwhile, has grabbed seven goals this term having fired the south Wales club to play-off glory last season.
Rodgers revealed talks with Britton are at a more advanced stage, but hopes to retain the duo, who are out of contract at the end of next season.
He said: "Leon is in discussions, there was a clause where if he played a certain number of games it was open for negotiation.
"His performances have been a reference for players of that type. Players who were discarded for being too small but who were highly technical.
"All the stats don't lie, it's not a dream anymore, he is making up to 100 passes a game which is phenomenal.
"He is 29 and we want to secure his future here. He is an honest guy and he gets what we are all about and his role is very important to how we play."
Of Sinclair he added: "Scott has made an incredible impact.
"He maybe hasn't scored as many goals as he would like this season, but he has done very well in terms of his contribution to the team ethic.
"We have opened light talks with him, we have not had a big sit down. He is happy here, I have touched base with him moving forward and hopefully between now and the end of the summer we can formulate a deal."
Last weekend's superb 3-0 win at Fulham was Swansea's third on the bounce, and a repeat against Everton this weekend would see them record their best run of top-flight results since the 1981-82 season.
But Swansea have never beaten Everton, and Rodgers is predicting a stern test against David Moyes' side.
"David has done a brilliant job there over a number of years and has made them very competitive and the team is a hallmark of what he has put in place," he said.
"No matter what team he plays they are hard to beat and breakdown, so all the positive elements of our game need to be in place, our possession game needs to be at a high level, our patience needs to be high and we need to take our chances.
"But we feel every home game is an opportunity for us with our wonderful supporters behind us here."
The Swans have also allowed midfielder Stephen Dobbie to join Blackpool on loan until the end of the season after finding first-team opportunities limited.