This is in response to a question I got through Twitter. I was asked: "Since I haven't progressed to composting yet, what's better for fruit peels and the like: garbage disposal or trash?"
Rather than reinvent the wheel, I'll just post a link to this answer to that very question. (Alex, if you want help tracking down the methane question, let me know. I'd be curious to know the answer for Portland. I'm currently tracking down the answer for Vancouver.)
However, I will also note that there's some other options. Just about everyone can compost. Composting with worms can be a little tricky, but can be done inside and with very little space. Composting outside on a balcony is also an option. Finally, there is the bokashi method of composting. Urban Farm School gives workshops on this and I'm planning on attending one in the future. I don't know a lot about it yet, but in the case of an apartment dweller, even if you don't have plants that would love the nutrients, you could easily give it away on craigslist. If you don't have many food scraps (which I'm assuming Alex doesn't) or if you're a lazy composter like me, you can freeze the scraps in a container until you're ready to compost them. There also might be a local community garden somewhere close that would take your food scraps (especially frozen-not already decomposing) and compost them. Ideally, food scraps will get composted. This is by far the best solution for them.
Thanks for the question, Alex! Keep 'em comin!