Title says it all. I submitted an abstract to a journal that publishes twice a year last April. Even now it still hasn't been reviewed. Should I take this as a sign that the paper is weak or should I just submit it to another journal?
The time involved in getting reviews does not indicate anything about the strength or weakness of your work. You should email to editor and ask where your article is in the review process.
If you want to send somewhere else, first write to the editor or use the electronic submission to unsubmit the paper from the original. I should add that with some of the electronic systems, the review process is actually further along than the system indicates because the editor/associate editor/people helping these people have not updated the information. So if you still want it considered there, write to the editor.