What kind of work are you doing now? Desktop applications? Web-based applications?
It really depends on what is your immediate need. I'm doing web-based applications mostly, so I'm going for SCWCD then SCJD. I could even skip SCJD and move on to SCBCD, it really depends on what my immediate need is.
The only developers I know who have gotten new positions solely based on certifications are those with the SCWCD or JBOSS/Weblogic EJB certifications. Short term, I would go for SCWCD as a good route for better employability. Long term, there is more money to be made as an EJB developer, at least in my market.