Study both. I know that English is more popular than French, but I studied French first , so I learn English. I studied VHDL in school but where I work, Verilog is prefered, so I studied Verilog
The US west coast and Asia prefer Verilog while US east coast and Europe mostly use VHDL. Verilog, with its latest IEEE1364-2001 standard seems to be widely accepted in future as compared to its counterpart VHDL.
I think compare Verilog and VHDL is just like comparing C and Ada, the former is ease to learn, and the latter is more difficult to learn, but they can do the same thing. In industrial, the Verilog is pop than VHDL. I know Verilog and VHDL, but I like Verilog.