Google Bundles is likely to be a good thing for classroom use, because it’s essentially the OPML idea with a catchy name (in fact, it looks like every bundle also creates an OPML file).
I don’t want to get into an argument about why things like Google Bundles and Twitter take off while things like OPML languish (one clue: OPML is a crappy, crappy name). If every Bundle produces an OPML file, I think we should postpone the religious war and promote this.
Google Bundles are a great way to turn sense-making and curating from concept to practice. I can see a teacher in a journalism ethics class selecting out the CJR feed, Jay Rosen’s blog, and a couple other sources and asking students to scan these for relevant posts. Bundles can also be used to pull together all the blogs created by students in a class, so that an institution with no internally provisioned Web 2.0 system (like Otago Polytechnic, for example) can reduce the administrative load of providing a way for all the students to see each other’s work — Bundles aren’t just for curators, but for peer groups as well.
Finally, I can see a group of people (whether students or staff) divvying up all the things they want to read into different bundles — Wendy and I will take Bundle A, Jenny and Mel will take Bundle B, Russ and Kim will take Bundle C, etc. Stories of interest that each group finds they can bookmark via delicious with a specific tag (which then flows it back into Google Reader). There’s less of this divide and conquer around than I’d like to see — Bundles might add a level of ease to it.
[And yes, the first person that says "You can do all this with OPML" gets flamed.... I know, you can. That's not the point.]