PS3 Pros
- Reliability
- Blu-Ray
- Lifespan (3+ years-till-obsolete)
- MGS4!!
- FREE to play online.
- Performance (debatable? - but proprietary 8-core processor is cool)
PS3 Cons
- Very weak market share (online not very busy + user community smaller)
- Price (generally higher + 360 can often be found used for DIRT cheap)
- Relative lack of game titles.
- Vibrating controllers an additional expense (if wanted)
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360 Pros
- Massive market share (3+:1, online ALWAYS busy, huge user group.)
- Generally cheaper.
- Twice or more titles available.
- More unique titles available (MASS EFFECT!! etc.)
- Stock controllers have vibration. (If you care)
360 Cons
- Very risky reliability. (Admittadly rushed into service a year early. Poor internal design. Overheats, 3RROD very common.
- Shamelessly abusive "addition" costs for decent HDD, Wifi adapter, intercooler, cordless kit, mic kit, etc etc...
- Xbox Live subscription fee is insulting. Points-based DLC setup is obviously rigged to force over-purchase of points and wasteful spending on stupid things (gamer icons etc.)
- Will be obsolete in 2 years.
- Xbox Live service auto-renews without asking. No way to cancel auto-renew without abhorrently torturous phone call to india. Will refuse to cease retention of credit card info unless you spend an hour beating it out of them.
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PS3 is probably the overall better machine but everyone seems to buy the Xbox anyway. I think the market share is what overrules every other rational decision-basing effect. Therefore, I would say the choice is probably based on how badly you want to play online. Xbox Live is flawed as hell BUT it is BUSY, PS3's online, while smooth and functional and free, just doesn't have the user volume to be competitive.
For primarily single-player or local-multi use (and if you intend to buy into blu-ray media for movies/tv shows) PS3 wins hands down IMO.