If you are using a pagination system, you're probably showing, for each page, a snippet of your items (news, articles, pages and so on). Thus, you're dealing with the famous duplicate content issue. In the page I've linked you'll find the solution to this problem too. In my opinion, this is one of the best thing you can do:
Use 301s: If you've restructured your site, use 301 redirects ("RedirectPermanent") in your .htaccess file to smartly redirect users, Googlebot, and other spiders. (In Apache, you can do this with an .htaccess file; in IIS, you can do this through the administrative console.)
A little note to the general discussion: Since few weeks, Google has been introducing a "system" to help they recognise the relationship between pages as you can see here: Pagination with rel="next" and rel="prev"
Said that, now I can go to the core of the question. In each of the two solutions, there are pros and cons.
As subfolder (page/1)
Cons: You are losing link juice on the page "page" because every piece (page) of your pagination system, will be seen as an indipendent source because they have a different url (infact you are not using parameters).
Pros: If your whole system is doing using the '/' as separator between parameters (which is in a lot of case a good thing) this solution will give coninuity to your system.
As parameter (page?param=1)
Cons: Though Google and the other S.E.s manage the parameters without problems, you're letting them decide for you if a parameter is important or not and if they have to take care to manage them or ignore them. Obviously this is true unless you're not deciding how to manage them in their respective webmaster tool panel.
Pros: You're taking all the link juice on the page "page" but indeed this is not so important because you want to give the link juice to those pages which will show the detailed items.
An "alternative" to pagination
As you can see, I posted on this website a question which is related to your. To sum up, I wanted to know an alternative to pagination. Here is the question (read the accepter answer): How to avoid pagination in a website to have a flat architecture?
