If it's that much of a trouble, then you just just use Mark's x-spot.

We use these when we don't know what speakers are going in and they've worked great especially when speakers aren't going in for awhile after the client moves in since you don't notice the plug and cost on them is less than $5!

[Link: scpcat5e.com]

maybe i'm cheap, but i have used strips of cardboard stapled to the inside of joist to hold the wire in place, then after drywall, I use 3/4" prewire plugs from GRI [Link: grisk.com] they can be painted and blend right in. cost is about $0.20 each.

As FunHouse mentioned, we run into lots and lots of those type pre-wire jobs where a single gang box is nailed up into the ceiling. All in a days work around here, some of you guys sound kinda pussy-ish if installing speakers in such a scenario is such a PIA. lol.

In our pre-wires we use speaker brackets or bury the wires and map it.

+1000

Do you have drywallers poke the wire thru the drywall, or do you end up 'blindly' drilling the 3/4" hole to install the plug?

i have the drywallers poke the wire thru the ceiling. the cardboard holds the wire where i want it. I cut the 3/4" hole for the plug and ask the painters to paint to match the ceiling. occasionally the hole the drywaller make is too big, so we get the painters or drywall finishers to mud them in.