ok...
- .mobi: this is basically an amway of TLDs. if you read the fine print, there are a number of restrictions for .mobi sites. granted some parking sites like sedo offer .mobi ready parking pages, but if you don't conform to their standards, you're out of luck.
- mobile content: this isn't content on the go. there are 2 issues. 1 is rendering. as you may know the phone in your pocket is different than the person next to you. even if it's the same model (e.g. RAZR) depending on the operator and region, the software stack will most likely differ. the biggest one is the browser. browsers are not unified and the key players (openwave and opera) are vying for total market control and thus drive their own standards. rendering WAP or mobile site pages is a huge hurdle and there are companies that address this specifically (Volantis' mobilizer product
http://mobilizer.volantis.net is a great tool to create mobile sites). The second issue is defining content types to meet device profiles. Similar to the rendering issue, not all mobile content (which by the way is defined as ringtones, screensavers, wallpaper, video clips...NOT content on the go) will run on all phones. Screen size, media support, and even operator gating procedures all impact if the content will run properly. Basically think of these issues as the old PC vs. Mac problem. PC content used to not work on Mac and vice versa. However, nowadays there are utilities that allow this. the mobile industry is very early from astandards perspective and we shouldn't see a unified mobile standard until 2008 at the earliest...
how's that?