Doesn't bug me, and Nvidia uses a recognizable numbering scheme.
ATi's cryptic model number codes are like saying forget off in response when someone asks about your card. Noone knows what they look like, or how good it is from them number, while Nvidia gives a small amount of indication.
In the past ATI has switched naming schemes (as has Nvidia) which may have caused confusion, however in recent times ATI has been more consistent in naming schemes than Nvidia.
This can most clearly be seen on the equivalent
ATI and
Nvidia Wikipedia lists. As you can see, ATI has been consistent in their naming structure since the R400 series of GPUs, starting with Radeon X700 through to the HD5970. The only major change was a switch from placing an "X" in front of the number to "HD".
On the other hand, Nvidia made a significant change when going from the Geforce 9 series to their G100 and G200 Series. To make matters worse, they continually rebrand their older models with new names (IE. renaming a 9-series card into a G200 series). A new confusion to add to the mix is that Nvidia just revealed that their new Fermi GPUs will be named as GTX 4--'s; whatever happened to the 3-- series?
Even if all of the above were not true, it is still childish to write off any brand of GPU based on some lack of immediate comprehension. If you are in the market for a potentially expensive item, you should be willing to do the research or suffer the consequences of missing out on better deals. If what your friends aren't familiar with ATI GPUs then I'd suggest purchasing and bragging about something more universal such as how much memory your computer has, or what capacity the hard drive is, or perhaps even what kind of car you drive.