Most external computer components are connected via USB. Although the connectors are versatile one issue is they aren't reversible. Sometimes it's hard to see which way is up and it's hard to know which way to plug it in.
TIVO made name changes to their Premiere lineup. The Premier XL has become the XL2 and the Premier Elite has become the XL4. The XL2 has 2 tuners and the XL4 has 4 tuners.