I've been trying to transfer my contacts from my old phone (Sony Ericsson w880i) to my new phone (Sony Ericsson X10). You'd think that being from the same company, and having a all-in-one suite from SE for phone operations (e.g. saving txt msgs, contacts, calendar entries, etc., etc.), that contact migration should be a breeze! Unfortunately, and most-disappointingly, the PC Companion migration feature requires you to transfer them through a google account. Not sure what would be needed if both phones weren't Android based, or if access to the internet wasn't available.
There's been various sites and forums that mention alternatives, but the only one I've found revolves around an MS Outlook contact list, which I also don't have. "What gives?!", I think to myself. Transferring contacts phone to phone shouldn't be this hard, especially if they're from the same company. Luckily, after playing around with the phones for a bit, I found the solution: vcf files over bluetooth. The w880 allowed for all my contacts to be saved into a vcf file, and both phones talk over bluetooth, and the X10 supports the reading, and interpreting of vcf files. Thus, the solution was discovered!
For the detail-oriented. The X10 was running Android 2.3.3. Not sure about the w880i (but it wasn't the latest version). So in conclusion, if you need to transfer contacts between phones, and you want to do it simply, quickly, and generally independent of phone manufacturer, look into vcf transfers over bluetooth.