Sitewide link gives you a lot more backlinks, it also costs more, but I've read here and there that it is actually worse that just a frontpage link. What's the deal?
while i'm making link exchange , i prefer making link exchange site wide . you get more backlink with this way
You know - site wide means better exposure for people. If you targetting in traffik so this is better option. If you add links to improve your serp position, then strong homepage is ok and not much power from links on sub-pages. G isn't so stupid to count all 'billion pages indexed' as one link...
The engines don't seem to be penalizing sitewide links yet - when they do, then switch to main page only links.
Why they should be penalized? They just will be not so important (if they are now, because I don't belive so much in it's power)