For anyone who wanted to why Weevil looks so "heavy" and full of acene these days, I've got your answer, courtesy of TVGuide's "Ask Ausiello".

Question: What happened to Francis Capra on Veronica Mars? He hasn't been looking too good.— Rachel
Ausiello: Many of you have written in asking about this, and here's the deal: According to Rob Thomas, Francis had a medical condition that's required quite a bit of medication, causing him to swell up and break out. The swelling has since subsided, and Francis returns in Episode 9 looking "lean and mean," Rob tells me. Some skin problems remain, but "he's feeling better, and it's just a matter of time before he's his old self."