It could very well have been taken with a vintage petzval lens, however there are many other lenses also capable of creating a similar swirling Bokeh effect as you see in this image. Ultimarely it is unlikely that you would be able to tell for sure which lens was used without asking the photographer.
Here is a list of a few other lenses that are famous for creating the "swirl"
- Helios 44-2 58mm F2
- Helios 44-6 58mm F2
- Helios 44-7 58mm F2
- Carl Zeiss 1Q Biotar 58mm f2 (10 blades version)
- Carl Zeiss 1Q Biotar 58mm f2 (17 blades version)
- Helios Cyclops 85mm F1.5
Recently a kickstarter campaign raised the funds to recreate Petzval lenses with modern mounts: http://microsites.lomography.com/petzval-lens/ Though they are not shipping to the public until June 2014 so I imagine that it is unlikely that the shot you linked was taken with one.