Many, many startups would disagree with you. If cost is a factor, we're starting a program for startups. Feel free to ping me for more info.
We'll also have a new developer license for our next release, which will make it easier for cash-strapped developers to use Splunk.
And finally, I would just point out that using rsyslog, syslog, and syslog-ng do not preclude you from using something like Splunk. Many of our users use Splunk with a log manager, such as syslog-NG, because they like our analytics engine and reporting tools. YMMV.
Now back to your regularly scheduled discussion :)
-John Mark Splunk Community Guy