@zorglub...its not 5 minutes of work for them because they only way you're going to get their attention is in a capital city and the trip is somewhat long. the chances of you getting an 85 to help you really slim. In Org, it took me 5 or 6 hours to get someone to run up to hyjal for me...and that's a QUICK hop. Org to Un'goro is too far for someone to do it as a quick favor (let alone alliance). That leaves you trying to get help within Un'goro, and that'll be borderline impossible because NO 85's are just going to be hanging out in Un'goro until you get their attention. Finding an 85 in a capital city to go all the way to Un'goro just to summon you IS possible, but it will probably take you days of solid work.
@babouchka...maybe, but i doubt it. Most will probably either fly there or are high enough that they can just run past without grabbing agro. 20's have a HUGE agro radius in there and un'goro has probably the highest density of mobs in all of kalimdor. I agree that hoping for a clear path is our best shot...but I think it'll involve a LOT of luck (even in the first few days).