Case in point: Canon’s new XD series to their long­time X0D DSLR models.

Lars Rehm and Richard Butler on Canon EOS 7D:

At first sight the 7D looks a lot like the EOS 50D and is unmis­tak­ably a mem­ber of the EOS fam­ily. However, a closer look reveals that on the new model Canon has made a few seem­ingly sub­tle changes that nev­er­the­less make a dif­fer­ence in terms of han­dling and oper­a­tion. The but­tons are larger than on pre­ced­ing models.

These changes to the con­trol lay­out, along­side the cus­tom con­trol menu, gives you more than enough options to fairly eas­ily tweak the inter­face for even the most spe­cial­ist require­ments and appli­ca­tions. The same is true for the new AF sys­tem which offers an abun­dance of AF point selec­tion and focus­ing options.

Read: Canon EOS 7D Review

PS. Talking about changes, rumor has been going around that Ricoh is about to intro­duce a sig­nif­i­cant update to their pop­u­lar GRD lineup, engad­get has some more info and pic­tures on the excit­ing new sys­tem.