Sesame Street seems to have had a penchant for parodying great* TV shows over the years, even though the references go way over the heads of their diminutive target audience.
*It's par for the course to write off the second season of Twin Peaks. In truth, while it does lose its way in the middle of it (after the conclusion of the Laura Palmer storyline), the momentum kicks back in towards the end. Furthermore, the Black Lodge sequence in the finale and Gordon Cole almost entirely make it worth it. Miami Vice's standalone episode structure inevitably lend it a mixed bag quality, while I agree with the AV Club line that the two latest seasons of 30 Rock are weaker than its first two. Mad Men has yet to hit sucky ground, and let's hope it never does.