As several of my LOST buddies can confirm, back in Season 3 I hypothesized that the island is an "axis mundi" or portal between the cosmic and earthly worlds. (The axis mundi can be represented by natural phenomena such as a column of smoke or fire, a tree or a well, or even a manmade structure such as a temple, ladder, lighthouse, obelisk - sound familiar?) Basically, it represents the "omphalos" - the navel of the world, a sacred place where all life begins. So when the glowing spring was revealed in "Across The Sea," I definitely felt that I had been on the right track all along. Though its significance has not been clearly articulated (and might never be), I like that DL & CC are going for big mythmaking and not merely "explaining" everything in scientific terms.
