bunltd - 4:02 am on Oct 15, 2010 (gmt 0)
Yes it's still useful. (if getting things indexed quickly is useful) Looks like the technorati address isn't the full address. And if we're talking WordPress, pingomatic is the default on all WordPress installs - and many folks never update this... and as such it's busy. Either of those things could cause delays.
[codex.wordpress.org...] has a list of other services you can ping.