banana peel is very overpriced in my opinion.
as for what to install; at this point, unless you have a customer that knows exactly what they're going to do with it, i don't think it matters much. because the vast majority of people have no idea what to do with this cabling. i'd still try to upsell on every job though, because it definitely has its benefits, but i wouldn't recommend going crazy with it.
an easy upsell is two coax's and two cat5e's behind the living room and master bedroom tv's, and a single coax and cat5e to other tv's. also two cat5e's to where a desktop computer may sit.
here is the pitch; directv requires two coax's for their DVR's (there is a way to do it with one cable, but DTV isn't giving it to existing customers, and very few resi customers, but you can purchase the single-wire multiswitch module yourself). Dish network requires one cable, but they have dual tuner receivers w/ RF remotes that can be used to send a separate feed to another room. You'll need that extra coax w/ dish network to feed the other room and avoid another receiver fee. i know this doesn't apply to cable TV, but most of my customers all have satellite as i'm in a rural area.
one cat5e is for a phone line to connect receivers (used for caller ID, PPV, and some updates to the receiver; if you don't have it connected, you might be charged extra). the second is used for networking; DTV and Dish use your broadband connection for on-demand video. But my favorite use for that cable is home-theater PC's. We use windows media center for 90% of our television viewing in my house. i've been introducing folks to it as its the greatest thing since sliced bread w/ a netflix account and hulu desktop plugings. i also have all our dvd's copied to a couple of TB's of HDD space, and we can pull up any dvd 'on-demand', as well as thousands of pictures, mp3 files, etc. . . . and we have the TV signal running through it.
the other rooms w/ the single coax and cat5e; you can use that UTP cable for a phone line to a receiver, or a network cable for a media extender. most likely a network connection, as many of the new gaming consoles their kids have connect to the internet for multi-player action, downloading games and trials, and can be used as media center extenders.