Time passess and women still squirt. yummy! I am wondering if any definitive source of the fluid
being squirted  has been determined.
Or is  it just urine?

And you might also want to ask LG about it, but, no, it's not urine although a little urine can mix in.  The fluid is stored in a sac above the G-spot and can be ejected with the contractions that occur during orgasm.

It is called the Skene's Gland or para-urethral gland. When you have your finger in a lady's vagina, about 1.5-3 inches in on the top side you feel a series of ridges. The glands are surrounding the urethra on the other side of the vaginal wall.

If you stimulate the area, with the lady at an appropriate level of arousal, you can often 'milk' the gland. The fluid is similar to prostate fluid. Depnding on the muscle development of her vagina and abdomen, a woman can expell the fluid on her own. I've had the opportunity to assist some ladies in 'awakening' their ability to squirt. Once a woman understands the feelings/sensations involved, she can focus on guiding to them during intercourse. It is pretty awesome to have a woman squirt on you while having sex. I went back and saw a few ladies who I had helped earlier, and the great thing is that the more they do and practice, the more fluid they found they can now squirt.

If you are a lover of DATY and slippery sex like I am, squirting adds a whole new erotic dimension, and for her, new orgasmic sensations.