Apple (Nasdaq: AAPL) has a formidable challenger on a specific Android model, according to mobile industry analyst Walter Piecyk of BTIG Research. After calling 150 Verizon (NYSE: VZ) stores to check their sales patterns, Piecyk says that the HTC Thunderbolt outsells the Verizon iPhone 4 more often than not.

So the mythical iPhone killer has finally arrived, right? Not so fast.

The caveats around this research are plentiful indeed:

  • Piecyk didn't call any Apple stores, where the iPhone surely would outsell a Google (Nasdaq: GOOG) Android model that would probably explode upon entering the store.
  • Best Buy (NYSE: BBY) stores sell both the Verizon iPhone and the HTC Thunderbolt, but weren't included in the survey. Would a Best Buy study yield different results?
  • The Thunderbolt is a Verizon-only model while the iPhone is available from AT&T (NYSE: T) Wireless as well. Add Ma Bell's haul into the mix and you'd surely get a different result.

Taking that last argument to its logical conclusion would open a rat's nest for Apple fans, though: Where do you draw the lines to define a model, a platform, and a sales statistic? Android as a whole is engulfing the iPhone family, but no single Android model can claim to have bested Apple's finest -- yet.

That said, the Thunderbolt seems roughly comparable to the iPhone 4 in most respects, but sports one defining advantage in its "4G" network connectivity. It would be in Apple's best interest to get 4G radio chips into the iPhone 5, thus erasing the Android advantage before it grows unmanageable. Since the Verizon iPhone already has a unique chip configuration, it wouldn't be hard to imagine Apple dropping an LTE 4G chip into the next refresh and eating the cost difference -- anything less would leave a lot of potential sales on the table.

Or will Apple's quest for perfection leave 4G-thirsty customers unsatisfied? Verizon's 4G coverage is in its early stages and will remain downright spotty throughout 2011. Also, LTE chips are still new, and run the risk of being bulky and consuming an undesirable amount of power. If Apple does in fact delay the release of the iPhone 5, as has been reported but isn't confirmed, that'd give probable chip partner Qualcomm (Nasdaq: QCOM) a bit more time to work on its LTE chipset designs.

Would Apple be better off delaying 4G iPhones until the summer of 2012, when the coverage maps have filled out a bit? Discuss in the comments below, and don't forget to add Verizon and Apple to your watchlist so you don't miss the final decision.