In the name of speculation, rumination and guess-timation, I have unscientifically compiled a "who's next" list when it comes to M&A activity in the wake of Google's $1.65-billion bid for YouTube. My methodology is admittedly simplistic and possibly prone to mistakes but it is Sunday morning. The "sources" for this list are ComScore and HitWise rankings and anecdotal evidence. It's open to criticism as well as suggestions. In no particular order, here goes:

1. Photobucket: With more than 25 million members, it's a surprise Photobucket hasn't been picked off like Flickr was by Yahoo. Photobucket raised $10.5-million in a Series B round led by Trinity Ventures earlier this year.

2. Facebook.com: It is just a matter of time before Yahoo pulls the trigger on a $1-billion acquisition? With MySpace part of Rupert Murdoch's Web portfolio, Facebook is ripe for an acquisition but what's the price. Clearly, Yahoo CEO Terry Semel is agonizing over this issue as we speak.

3. Gorilla Nation: an online ad sales representation firm that handles media sales for more than 250 high-traffic Web sites. In August, it was the 22nd highest-ranked Web site in the U.S. with 25.9 million unique visitors.

4. Weatherbug: Another highly-ranked Web site (40th in unique visitors), Weatherbug has 8,000 tracking stations and 1,000 cameras throughout the U.S. It's also got a bad reputation as a purveyor of spyware.

5. CareerBuilder: A popular job site that was the 29th most popular site in the U.S. with 20.6 million unique visitors in August.

6. Digg.com: Another one of those Web 2.0 start-ups ripe with takeover potential, it seems to be only a matter of time before a deal materializes.

7. Technorati: Maybe Technorati's time has come and gone. If it was going to be acquired, it might have already happened. Then again, blogs are still in their relative infancy so a tool to track traffic could be pretty valuable. I still think Google is a potential suitor given how underwhelming Google Blog search has been since its launch.

8. FeedBurner: After establishing its as one of the leading RSS publishing services/tools, FeedBurner's appeal will only increase as RSS becomes less of an acronym and more of a mainstream tool embraced by people who want to easily personalize content.

9. Heavy.com: a popular video-sharing service that cheekily bills itself as the "#1 broadband destination for wasting time". According to HitWise, Heavy was the second most-popular video sharing service in the U.S. during the first week of October with 17% market share.

10. Zoho: If the Web 2.0 office suite and the Office 2.0 movement actually take root (propelled, in part, by Google's efforts), Zoho could become an appealing target.

11. WordPress/Typepad: Blogging is only going to get bigger so it makes sense that two of the most credible players could be snapped up.

This list, of course, is incomplete so if you have suggests, fire away. There are lots of other people thinking about the same topic such as Tech Trader Daily and Tolman Jeffs, managing director with the Jordan, Edmiston Group.  For some perspective, Tristan Louis also put together a list of recent Web 2.0 acquisitions. CNet, meanwhile, has a list of some high-profile Internet deals that succeeded and failed. As well, the New York Times has a sad tale of how Friendster founder Jonathan Abrams turned down a $30-million takeover offer from Google in 2002. If Abrams had accepted the offer, he would have received pre-IPO Google shares that now might be worth $1-billion.