The first phone to implement Google's Open Source Android mobile platform — the eagerly-anticipated T-Mobile G1 — made its maiden voyage today, launching to the expected fanfare and with the surprise appearance of Google founders Larry Page and Sergey Brin — on rollerblades.

Developed by Taiwanese manufacturer HTC as the Dream, the G1 is Google's first volley in the ever-increasingly hostile mobile phone wars. The phone carries with it Google's reputation — with the search giant's logo conspicuously placed on the phone's case where the manufacturer's normally would be — as well as its noted prowess in launching things the computing public will find indispensable. The inevitable comparisons to Apple's iPhone have already begun, in many cases painting the G1 as nothing more than an Open Source copy.

However, the G1 is its own creature, with noticeable differences, many no doubt learned from the public reception of the iPhone. Like Apple's device, the G1 offers an online marketplace where individual developers can provide applications to users, but unlike Apple, Google's market is open to anyone, without an annual developer membership fee or corporate approval. The handset itself is a hybrid of best features, offering both the iPhone-style touch screen and a full slide-out keyboard à la T-Mobile's Sidekick, and runs both on T-Mobile's newly-upgraded 3G network and Wifi. The Android install comes with Gmail and YouTube support, as well as a Google Maps with Streetview install that integrates with the handset's internal compass to offer a 360° street-level view of wherever the user happens to be standing — provided, of course, that the street view cameras have been by.

Three pre-loaded applications from the winners of Google's Android Developer Challenge are included as well: ShopSavvy, a barcode-scanning price checker, Ecorio, a carbon footprint calculator, and BreadCrumbz, which offers visual maps created step-by-step with photos. While there is no support for files protected by DRM, Amazon is offering an application that integrates with its online store, allowing users to buy and play music directly on their G1. Undoubtedly, the application market will offer scores of media options, undercutting any issues with DRM.

The handset, which can be pre-ordered online by existing T-Mobile customers starting today, will actually appear in user's hands beginning October 22. Priced at an iPhone-undercutting $179, the phone requires either a $25/mo mini-data plan, or a $35/mo unlimited plan — given the features involved, the latter is likely to be popular. Whether it will prove an "iPhone killer" or not remains to be seen, but perhaps the bigger question is, was it ever really meant to?