take a look @ yoast and his comments on pagination..
also take a look at a page 2 in xenForo forum's thread. i like how they do SEO.
they do it same way

now IPB does it differently by prefacing the description ( 1st post ) with page x of y -
that is to make it look 'different' as to not have duplicate content descriptions.. but in looking closely their og:description is the 1st post of that page too (
Example )
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so, in the end, i sided with Yoast ( SEO guru ) and the newer forum platform xenForo
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also, iteration #2 will probably have an admin back end, where you can select certain things like: analytics, pagination style, apple iTouch icons, og:image .. rel="next" rel="previous" rel="canonical" og:site_name and more..
this is iteration #1 and gets the main og:xxx's out of the way to make it much easier for googlebot to grab SEO from the <head> section, vs wade thru table, tr, td stuff to figure it out.
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now if you want to have 1st post as description for every page, just modify showflat.inc.php where it does $ogDescription and voila

ubbDev for the win !