Similar to the above, I am about to be 28 and I applied for a PhD for the fall, so I will be well into my 30s by the time I finish! I won't be a spring chicken when I'm done, but the up-side is that I feel much more focused than out of undergrad and even out of my first grad program...
but I know it's hard to feel hopeful it's more competitive than ever, but don't let the age thing make you think you can't give it a another shot. (my mother, btw, finished her BA in her thirties, phd in late thirties, and then finished a second phd in her late 50s/early 60s!)