Recent analyst reports would suggest that despite Nokia’s best attempts to boost sales of its new Lumia 800 Windows Phone handset, the device has failed to live up to predictions, resulting in the slashing of sales estimates.

Pacific Crest analyst James Faucette suggests that Nokia will not ship the 2 million Windows Phone units it had forecast in the final quarter, leading Pacific to cut estimates to less than 1 million for the same period. To compound matters, its checks found “disappointing sales” for the Lumia, with December sales estimated to be less than 500,000 units.

Moving quickly to dismiss the research note, Nokia today issued its own piece of specially crafted marketing spin:

“Lumia 800 sales in the UK are off to an excellent start. Based on earliest data the sales start of the Lumia 800 is the best ever first week of Nokia smartphone sales in the UK in recent history.”

“By our measures, we have gained significant smartphone sell-out share in the channels in which we are operating in the UK”

So Nokia’s new smartphone is performing well? We still don’t know.

Nokia’s carefully-worded statement says all the right things without saying very much at all. Lumia 800 sales are “off to an excellent start”, it’s the “best ever first week of Nokia smartphone sales in the U.K in recent history” and it has “gained significant smartphone sell-out share” in the channels in which it operates in the U.K.

An excellent start could mean literally anything — if its internal estimates were conservative, then better-than-expected sales could be perceived as an excellent start. Given today’s smartphone market, you would expect Lumia 800 sales to outpace those of the Symbian-powered Nokia N8 and associated N-Series smartphones.

The company has concentrated on the UK with its Lumia 800 launch, running a multi-million pound marketing campaign which includes TV, print, online and music launch events.

As GigaOM notes, Nokia hasn’t set out to blast the smartphone market wide open with the Lumia 800, the handset is just the first of a long list of devices that it hopes can help it climb back into the smartphone race and compete with Apple, Samsung and HTC.

It’s difficult not to agree with GigaOM writer Bobbie Johnson’s assessment of Nokia’s predicament:

Don’t get me wrong: the stakes are tremendously high for Nokia here. Every statistic deserves to be scrutinized, every announcement should be pored over, every report has some weight to it — and if Nokia gets this totally wrong, it could be a long term problem that is near-impossible to recover from.

However, Nokia isn’t lying when it says it is gaining significant smartphone sell-out share. Many Orange stores in the UK are experiencing limited stocks of the Lumia 800 — Microsoft’s James Strutt posting photo evidence of one such store in Birmingham:

 If Nokia’s Lumia 800 sales are poor, its working hard to portray the opposite

Nokia will face a lot of scepticism as it begins to roll out its new suite of Windows Phone handsets. With the Lumia 710 next to launch at a more competitive price and word from Nokia representatives that CES 2012 will be the next time we get to see more devices from the Finnish mobile giant, the company still has plenty of chances to convince the consumer that it has got what it takes to deliver devices capable of competing with its more established smartphone-making rivals.