Probably not. Apple may limit Handoff to built-in bluetooth only.
There's already a precedent with PowerNap: it only works with MBAs and rMBPs that have always shipped with factory-installed SSDs. There's technically nothing preventing my 2009 MBP 13" with Samsung SSD from having PowerNap (since its firmware already supports Dark Wake mode), except for Apple's refusal to do so.
Speaking of SSDs, Mac OS X supported TRIM command since version 10.6.6 or so, but it artificially limits the feature to those that identify themselves to the system as "APPLE SSD". Of course, there are utilities that patch the system driver so that 3rd party SSDs work with TRIM, but still.
Another example: in iOS 3.0 (then called iPhone OS) Apple caved in to demand and added support for MMS, however it was limited to iPhone 3G and 3GS, leaving out the original iPhone. So the jailbreak community quickly discovered that one of the system frameworks had a check for model version, basically saying: "if you're not iPhone 3G or newer, then no MMS for you!" There was also a patch that enabled MMS on jailbroken 2G iPhones, proving that all required support was already in place.