In my case, it isn't just a few grams. The difference in weight between a 2006 Campangolo Chorus triple crank and a 2011 Chorus compact is 330 grams. However, it isn't the weight savings that has me interested in moving to a compact. The shifting will be better on the front dr. The new Campy 11 speed also shifts better on the back because the cogs are closer. 98% of the time I can ride in just the big chain ring and here is why:

I have a 53/42/30 triple with a 13/26 on it.

A 42 X 26 on a triple is the same as a 50 X 29 on a compact; a 53 X 13 on a triple is almost the same as a 50 X 12 on a compact. The 50 X 12 is a slightly larger gear which is an advantage. So, the 50 on the compact will replace both the 53 and 42 chain rings on the triple. For climbing gears, a 34 X 29 is the same as my current 30 X 26. So, I am not losing anything at all. I am losing 330 grams off the crank alone. I suspect that I will loose even more off of the entire group.

As for the age, I am 53 soon to turn 54. I too needed a triple when I first started riding 4 years ago. I no longer need the small chain ring. However, going to a compact will give me the same gear ranges with few gears.

You will never use all 30 gears on your triple, you will use a range of gears. For example, you will use the first 2 or 3 gears on the small chain ring and maybe the last 2 or 3 gears on the big chain ring. With a compact, you will use all of the gears.