Yes, Lr 4.1 and ACR 7.1 have the ability to import and render floating-point HDR images. Supported formats are TIFF and DNG. (If you have HDR images in other formats like OpenEXR or Radiance, you can use Photoshop or other tools to convert them to TIFF.) Supported bit depths are 16, 24, and 32 bits per channel.
If you're using Photoshop's Merge to HDR Pro feature to perform the "merge" step, be sure to choose 32-bit output in the top-right popup menu of the HDR Pro dialog box. This will generate a floating point (but not yet tone-mapped) image, which you can then use ACR or LR to render and tone map using the new PV 2012 controls.