I have been playing with both the iHttpHandler and iHttpAsyncHandler lately, and I came across some interesting information. There are a couple of blog posts out there explaining when to use one over the other (see Mads Kristensen's post here, or Vlad Hrybok's post here) So when does it make sense to use Async? Consensus seems to be that it makes sense to use the iHttpAsyncHandler for long running operations, so while it probably doesn't make sense to use an iHttpAsyncHandler for say, loading images,...