If it could be done safely, then of course it's much better to sync my data onto the web because then I can access it anywhere but the downside is that you really have to trust the company, if you're expecting any of it to be kept private. On the technical side, my level of google trust is high but on the political side, not so much. Firstly they're in the States and my data is therefore going to be subject to any search and seizure laws passed over there, not over here. Not that Bush would find much of interest in my calendar but I still don't want him turning up at my parties unannounced. I'm also aware that Google, certainly in their search department, are very bad at de-caching any data which was once public but has now been changed; I'm hoping that if I manage to make a tiny error over event security, I won't then have to contact the behemoth to have it un-cached once I've fixed it. My assumption is that because they control the source data they'll be better about this than they are in web search. There's not much I can do about the location side of it unless I want to install a calendar app on my own website (or write one, I suppose or, even better, host my own webserver and run one on that) which doesn't seem likely. At heart I'm not a server admin and I just don't want it enough to put that much work into it.
In this case, the trust problem is made slightly more complicated by the fact that I'm not actually able to sync my phone directly with my google calendar. Instead, I'm going through a middle man - ScheduleWorld. This synchs with my mobile phone using the SyncML data standard*. It then has special settings for synchronizing with Google via their API. It sounds a bit laborious but in fact, once it's set up there's very little to it. I set my phone to sync once per day and I can manually sync too if I want. Then set ScheduleWorld to sync with Google every time it gets a request from my phone and I'm done. It's pretty neat, and, for someone as chronically forgetful as me these days extremely useful.
* I was AMAZED to find that not only is there an open standard for transfering this data but it is supported by most of the big mobile phone manufacturers! Just exactly what you hope for and so rarely find :)
** Speaking of s2, coffeechica, your style is nearly in a useable state now - archive, minical, and reply page all in (all subject to your picking things about if you want, of course). No page nav on entry pages or killfile yet but other than that, it's getting pretty close.