: Creator Shonda Rhimes noted that Denny's appearance in this episode was meant to represent "Death," which is why he wore black and spoke sparingly compared to previous appearances.
: Jeffrey Dean Morgan makes a final appearance as Denny Duquette, appearing as a hallucination to Izzie that Derek and Bailey eventually realize is a symptom of her worsening condition. Behind the Scenes Facts
: After Derek and Bailey discover that Izzie has an inoperable brain tumor, the group decides to celebrate her life and love immediately. [S5E22] What a Difference a Day Makes
: Despite the shift in plans, the wedding remains a fan favorite, featuring the original "MAGIC" interns (Meredith, Alex, George, Izzie, and Cristina) as the wedding party.
: Rhimes described the episode as the moment Meredith evolved from a "dark and twisty" girl into an "extraordinary" woman capable of choosing happiness. : Creator Shonda Rhimes noted that Denny's appearance
: Alex delivers a powerful, spontaneous speech adapted from a valedictorian's graduation address, promising to be accountable to Izzie through any future challenges. Medical Drama and Character Growth
In , the Season 5, Episode 22 milestone titled " What a Difference a Day Makes " is a landmark 100th episode that originally aired on May 7, 2009. It is widely celebrated for its emotional depth, shifting from a planned grand wedding for Meredith and Derek to a poignant ceremony for Izzie Stevens and Alex Karev. The Unexpected Wedding : Despite the shift in plans, the wedding
: To promote the 100th episode, ABC created a real wedding website for Meredith and Derek that fans could actually visit and RSVP to.