There have been a number of significant announcements lately around the topic of mobile search advertising.

Just over a week ago the folks at Yahoo! announced they would begin embedding sponsored ad links in mobile search results.

Not to be outdone, this week MSN announced they would be extending the Windows Live Search sponsored links model to the mobile search market. In both cases advertisers would bid on keywords using the auction model that has become so popular lately.

As if to justify these announcements, a report came out recently indicating that mobile web users are significantly more accepting of targeted ads than non-targeted mobile ads.

Going against the grain, Ask.com just announced that they have launched their own mobile search service, without any advertising, at least for now. What's interesting about the Ask.com solution is that they actually reformat the sites linked to in their search results to fit on small mobile screens using technology from Skweezer. My initial tests resulted in Gateway Timeout errors however, so I can't really comment on the effectiveness of this approach.