Stating the obvious: since many nice blogs by grad students and/or recent math PhDs have popped up recently and since there’s no reason for this trend to slow down (all the more since there seems to be nobody from places like Harvard, Orsay, Tokyo, Princeton, Oxford, etc. yet and surely they’ll join in), well my guess is that in, say, six months time, there will be way too much interesting stuff to read per day than is humanely possible.
And at that point this will mean people will have to choose carefully which blogs to read or not to, just to have a chance of catching up with what goes on there while still devoting most of a day on one’s own work. Put differently, we will need a kind of generic math blog server akin to the arxiv which would collect all known feeds and were new bloggers would submit theirs, rather than us blog readers having to manually search new feeds for our aggregators.
Am I right? If so there seems to be little chance that the arxiv could offer this since already for trackbacks things are quite experimental and require some manual control. So: where and who could set up this math blog referencing tool?
Other things that can be anticipated: enthusiastic grad students speaking too much about their unpublished projects and seeing a few weeks later somebody with a preprint exactly about that… What else? An environment which would help ideas to cross from one area to another faster and more easily than 30 years ago. But stronger trends/buzzwords effects too, probably.