Oliver leans towards "entertainment" than "information" in my experience. There's a time and place for entertainment, but I definitely need to double-check his facts before relying upon them.
Some of Oliver's arguments are "weak", feeling like he's sometimes padding for time. With that being said, Oliver is far better at this format than say... Bill Nye. (I was... saddened, by the weak treatment of subjects on that show)
Colbert seems to be focusing more on a typical late-night formula (talk with celebrities to promote books and movies, primarily on "safe" subjects: see his "Meanwhile" segments, which are hilarious but otherwise pallet cleansers). Colbert barely has much more than 5-minute talks on any political subject these days... a good thing for the mass-audience, but too short to really dive deeply into a subject matter outside of highlighting a few headlines.
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Overall, Oliver is one of the better shows in this category. But certainly has its flaws. No one really beats John Stewart, who really mastered the segment and earned my trust. (Stewart even had to do this in a far more difficult setting: once per night, 4 times a week. Oliver only has to prep for one segment per week). Stewart certainly had his mistakes, but he also humbled himself with constant reminders that Stewart was a "sad clown", reminding the audience that his skits were primarily driven for entertainment (even if large bits were educational)
The main difference between Oliver and Stewart is that Oliver seems to have fewer self-deprecating bits, or reminders that Oliver is primarily a sad clown as well. Entertainment outrage... relatively well researched, but still entertainment nonetheless.
Maybe I should watch Trevor Noah and see how he's keeping up the old Stewart timeslot.
> He's obviously too biased to have a fair view.
Stewart was biased, but overwhelmingly fair in my experience. Yeah, he leaned left, but no one can deny their own personal bias on political subjects, and that's fine IMO.
Oliver is biased, but IMO isn't as fair as Stewart in all subject matters. Fortunately, Oliver is "fair enough" and still has a decent show.
It's an educational/advocacy show with a veneer of comedy.