I remember quite the cheering when Sojourner
landed as well. With it it was a unique craft they were landing on Mars with a even more unique method (drop it and hope these airbags prevent things from breaking.) With Spirit
there was some measure of assurance things would work as there wasn't anything too unique or risky about what they were trying after success of Sojourner
Here with Curiosity
... Well, given how complicated the "landing" process was with everything needing to work and needing to pretty much work perfectly
, yeah, it was quite the accomplishment when everything worked perfectly.