If this goes on, pretty soon all garage door openers will have CPUs over 1Ghz and no self-respecting citizen will have less than 512MB of RAM.
The real elite will have scalable, enterprise-ready cloud-based garage door opener backoffice systems with parallel processing capability and huge scalability.
A good reason to go with the RasPi and a commodity USB Wi-Fi adapter here is that it will very likely end up cheaper than an Arduino (clone) plus a Wi-Fi shield. The latter can cost up to $90 [1]. Depending on where you live a TP-Link TL-MR3020/TL-WR703N wireless router might be a cheaper alternative to the Pi that has both Wi-FI and GPIO on-board but it is a bit more of a hassle to wire up.
The real elite will have scalable, enterprise-ready cloud-based garage door opener backoffice systems with parallel processing capability and huge scalability.