I would also love to see this functionality. I’ve got a similar need, with a site for a number of schools and would love to be able to add a subscribe option for just a particular school (each school has its own blog category).
I’d be curious to hear responses to this question as well, since I’m currently using 1.5 on PHP5. The problem I’m having is that it’s slower than it was under PHP4, to an insane degree. I haven’t gone digging as to why yet (could be MySQL, GD2, or who knows what). But, for whatever reason, page loads are exponentially slower than they were on the same server under PHP4. Everything seems to work OK beyond the slowness of things, though.
