28 Days Later is one of my faves. Its "cheesy" quality was part of its appeal, especially in theaters. It was odd for having been shot on videotape. It's harder to tell when you watch it on your TV (at least my lo-def TV) but it was an unusual sight in the theater, all the subtle differences in cinematic feel blown up large. For example, the sky tended to glow brightly and cast a fringe on the outline of the landscapes under it -- something we might see all the time in our home movies without noticing it, but weird to see on the big screen. I recall it took me a few minutes to get used to the home-video look when I watched it the first time.
After a while I think it achieved the intended effect of seeming a little more immediate and unpolished, like a documentary, as if updating the original Night of the Living Dead approach of using cheap black and white photography, apparently shooting with no sound and looping all the audio, slapdash camera work and lighting, etc. for it to feel more immediate within its own time. While Romero's flick had some amateurish acting, the cast of unknowns contributed to the naturalistic non-Hollywood feeling, and so did the lack of big stars (as of its making) in 28 Days Later.
So I'm a little nervous about being disappointed with this sequel. No Danny Boyle direction, none of the same characters... and I know I'm pretty much the only one who cares, but the previews do not look like they were shot with a cheap video process.