(Where's Michael Buffer when you need him? "Let's get ready to ruuummmmbbbllllleeee!!!!!)
Does size matter? It might for some, but these two combatants are pretty close when it comes to size and weight. The iPad Mini measures 7.87 x 5.3 x 0.28 inches and the Nexus 7 measures 7.81 x 4.82 x 0.41 inches. The length and width are nearly the same, but in terms of percentages, the thickness is nowhere close. The iPad Mini is 7.2mm thick and the Nexus 7 is about 31% thicker at 10.42mm. The iPad Mini weighs 10.9 ounces (308 grams) and the Nexus 7 weighs 12 ounces (340 grams). The Nexus 7 is about 10% heavier. The iPad Mini is slightly thinner and lighter, but taller and wider. Advantage: iPad Mini.
The iPad Mini's display measures 7.9 inches and has 1024 x 768 pixels for a pixels-per-inch density of 163. The Nexus 7's display measures 7 inches and has 1280 x 800 pixels for a pixels-per-inch density of 216. The iPad Mini's display has a 4:3 aspect ratio and the Nexus 7 has a 15:9 aspect ratio. The iPad Mini has more viewable real estate, but the Nexus 7 has a higher-resolution screen. Advantage: Nexus 7.
Apple's 1-GHz dual-core A5 chip powers the iPad Mini. It is (probably) mated to 512 MB of RAM. The Nexus 7 uses Nvidia's Tegra 3 chip with four cores operating at 1.3 GHz each. The Nexus 7 has 1 GB of RAM. The iPad Mini boasts 10 hours of battery life, as does the Nexus 7. Advantage: Draw.
The iPad Mini has a 5-megapixel iSight camera. It can also capture video at 1080p HD. The front camera shoots 1.2-megapixel images and can capture 720HD video for FaceTime chats. The Nexus 7 does not have a rear camera, but it's front camera also shoots 1.2-megapixel images and captures 720p HD video. Advantage: iPad Mini.
The iPad Mini comes in two versions -- one that only has Wi-Fi and one that pairs Wi-Fi with one of three different LTE networks. LTE 4G, of course, lets the iPad Mini surf the Web wherever AT&T, Sprint, or Verizon Wireless provides network access. The Nexus 7 only has Wi-Fi, no 3G or 4G. That means it can only be used to browse the Web within range of a Wi-Fi hotspot. Advantage: iPad Mini.
The iPad Mini comes in three different storage configurations: 16 GB, 32 GB and 62 GB. Right now, the Nexus 7 comes in two storage configurations: 8 GB or 16 GB. This is expected to change as soon as October 29, when Google announces new Nexus gear. For now, however, Advantage: iPad Mini.
The iPad Mini has access to 275,000 dedicated tablet applications in the App Store. That's a lot of apps. The Nexus 7 can use most apps in the Google Play Store, but the vast majority of them are not optimized for the tablet form factor and may offer a less-refined experience. Advantage: Draw.
The iPad Mini starts at $329, but ranges all the way up to $659 depending on options. The $329 option provides 16 GB of storage and Wi-Fi (no 4G). The Nexus 7 costs $199 for the 8-GB version and $249 for the 16-GB version. Advantage: Nexus 7.
Based on these criteria, the iPad Mini comes out ahead of the Nexus 7 in terms of specs. But the price difference is significant enough that it's hard to call a clear winner. Whichever of these two tablets you might pick, both will provide a solid Web-browsing and app-running experience.