I think playing YHOO as a way into Alibaba is a good move.
Some analysts believe YHOO is undervalued by several billion even though their core business is almost non-existent.
YHOO is not going to sell as many of their BABA shares as they were originally obligated to so YHOO shares stands to gain should BABA do well.
It is believed YHOO will do either a share buyback or cash dividend with at least 1/2 of the cash they get from the BABA IPO.
Not much is known in regards to what Marissa is going to do with the leftover cash from the BABA IPO so it might be a wise move to parlay the profit from YHOO into BABA shares post IPO (wait for moment of weakness).
The x-factor is whether a company decides to acquire YHOO pre OR post BABA IPO which could offer added value to YHOO shares.