Since the beginning of the year, Apple shares have more than doubled from $90.75 on Jan. 2 to almost $186 today.

Google (GOOG) has done about half that performance, while Microsoft (MSFT) has done one-third. (See the chart below; click on it to make it larger.)

But that’s apparently not enough, according to Thomas Weisel analyst Doug Reid, who has raised his price target on Apple (AAPL) stock to $210 from $180 a share.

Citing higher sales and profit estimates, healthy demand and the iPhone headed to China–and the launch of a cheaper $800 MacBook soon–Reid wrote, “We believe there is a high likelihood Apple will fortify its entry into the holiday season and that such a move will be a positive for AAPL shares.”

While this all makes sense, one wonders if the froth can reach that level.

In any case, perhaps what is more interesting is the $166.4 billion market cap for Apple, which is well below Microsoft at $232 billion.

But it is well above Hewlett-Packard (HPQ) at $113.4 billion, Google at $158 billion, Dell (DELL) at $30.6 billion and Palm (PALM) at a paltry $2.4 billion.

With that kind of massive valuation and a pile of it in cash, perhaps the better question is what Apple will do with its soaring stock.

Oddly enough, Idina Menzel and Kristin Chenoweth singing the big number, “Defying Gravity,” in the musical, “Wicked,” sound a lot like they are channeling Apple’s corporate mantra these days.

Witness:

A report in the Times of London in which Microsoft would buy Yahoo’s search business in a convoluted $20 billion deal that would include well-known Internet execs Jon Miller and Ross Levinsohn, is–in the words of one key player–”total fiction.”

Actually, that’s Levinsohn speaking, on the record. But that’s also the essential word from all key players regarding the Times’s report.

BoomTown has spoken to top sources at Yahoo (YHOO) and Microsoft (MSFT) too and all scoff at such a deal now taking place or that either side has been in any such discussions of late.

Yahoo’s entire market cap, in fact, is only $16 billion.

Rumors of Microsoft buying all of Yahoo have popped up regularly since it abandoned its failed takeover bid, all of which have been untrue.

That’s not to say there will not be some search deal between Yahoo and Microsoft, which seems more than likely at some point.

It makes sense on many levels and is supported by Carl Icahn, the Yahoo board member who upped his money-losing stake in the company last week.

That stock purchase should be enough of a reason for there to be no Microsoft-Yahoo search deal imminent, given Icahn would be more than well aware of it and buying up almost seven million Yahoo shares–now at historic lows–only days ago would smack of insider trading.

Still, the report in the Times has an unusual level of detail, involving Microsoft giving large gobs of money to Levinsohn and Miller.

Wrote the Times:

Under the terms of the proposed transaction, Microsoft would provide a $5 billion facility to the Miller and Levinsohn management team. The duo would raise an additional $5 billion from external investors.

This cash would be used to buy convertible preference shares and warrants which would give it a holding in excess of 30% of Yahoo.

The external investors would also have the right to appoint three of Yahoo’s 11 board directors. The talks with Yahoo involve Microsoft obtaining a 10-year operating agreement to manage the search business. It would also receive a two-year call option to buy the search business for $20 billion. That would leave Yahoo to run its own e-mail, messaging, and content services.”

Sounds good, except it’s the first time Levinsohn has heard of the plan, he said. Sources at Microsoft and Yahoo also said there was no deal like that in the making at this point in time.

Earlier this year, there was also another deal involving Icahn, before he gave up his proxy fight against Yahoo in exchange for a board seat, which did involve Levinsohn and Miller taking over Yahoo.

But, as has happened to many schemes involving Yahoo, it never came to pass.

Interestingly, there was also a similar investment deal as the one described in the Times, many months ago, just after Microsoft had walked away from its takeover battle for Yahoo.

It involved a very complex transaction involving Microsoft buying a large stake in Yahoo shares, running Yahoo’s search business for a time period and giving Yahoo a huge guaranteed revenue stream.

But that deal had already been spurned by Yahoo for the search-ad deal with Google (GOOG), which collapsed recently under intense regulatory scrutiny.

That has focused a lot of attention back on a possible deal between Yahoo and Microsoft, the No. 2 and No. 3 players in search, both of which have been chasing Google without any success.

Microsoft, despite spending billions, has been lagging badly behind Yahoo, which has more than doubled its share.

And that is precisely why it has long been interested in acquiring Yahoo’s search business.

Microsoft CEO Steve Ballmer has said the software giant is not interested in buying Yahoo many, many times, although he has not ruled out a search deal of some sort.

But Microsoft, many sources said, has been waiting for Yahoo to get another CEO in place, after Yahoo CEO Jerry Yang recently said he was stepping down to make way for a new leader.

Yahoo has also said in recent days that it is not currently engaged in any kind of talks with Microsoft, even about a more likely search deal.

At least in this chapter of the drama that has engulfed Yahoo over the last year, believe them.

[Full disclosure, though run separately, The Times of London is owned by News Corp. which also owns this Web site.]