I know I have read this somewhere and I wonder if it is correct. When the fellowship comes out of Lothlorien it is implied that, during the time it has taken for them to be in Lothlorien, a lot more time has passed in the world outside. The fellowship don't realize this themselves, it is supposed to be implied by mentions of the moon cycle. Link to timeline for tLotR.
I believe that any references to the passing of time in the book are merely meant to show that the peacefulness and isolation of Lórien made them forget their task and their urgency (not to mention ease the hurt of losing Gandalf).
"They remained some days in Lothlórien, so far as they could tell or remember." (Book II, Chapter 7)
And as they are leaving:
"Their hearts were heavy; for it was a fair place, and it had become like home to them, though they could not count the days and nights that they had passed there." (Book II, Chapter 8)
Although there is a slightly longer and more specific passage between Legolas and Frodo the night before attempting the rapids. Sam is trying to figure out how many days they stayed in the company of the Elves, but is having trouble reconciling his memory with the phase of the moon:
"Legolas stirred in his boat. 'Nay, time does not tarry ever,' he said; 'but change and growth is not in all things and places alike. For the Elves the world moves, and it moves both very swift and very slow. Swift, because they themselves change little, and all else fleets by: it is a grief to them. Slow, because they do not count the running years, not for themselves. The passing seasons are but ripples ever repeated in the long long stream. Yet beneath the Sun all things must wear to an end at last.'
"'But the wearing is slow in Lórien,' said Frodo. 'The power of the Lady is on it. Rich are the hours, though short they seem, in Caras Galadhon, where Galadriel wields the Elven-ring.'" (Book II, Chapter 9)
It's hard to figure out what the truth is here. Legolas seems to believe that the trouble is simply one of memory in such a place. Frodo, who knows Galadriel possesses the ring Nenya, seems to think there's actual magic somehow changing the passage of days within Lothlórien. As far as I can tell, it's left unresolved (especially since the person who would probably know best, Gandalf, the bearer of Narya, was unavailable to give his opinion).
Time in Lothlorien passes differently than in Middle Earth.
Quote from The History of Middle-earth - The Tale of Years:
The Coy. [Company] stays in Lórien for many days. They cannot count the time, for they do not age in that time, but outside in fact 30 days goes by.
They cannot count the time, for they themselves do not age or only very slowly. Outside in fact about 30 days passes.